"Operation QSL" : Letterpress QSL Cards for the Vintage Station.

I thought "Surely . . . surely, in this world of re-invested technology from the past, in a world where the ancient Letterpress has come to almost dominate the Wedding Announcement / High End business card / Premium Stationery market . . . surely someone out there is regularly addressing the Amateur Radio community with QSL cards that correspond with the vintage/ quality/ nostalgia factor that obviously drives the "Boat Anchor" crowd.

I am amazed at the multiple thousands of vintage radio dollars which are exchanged daily either over or via eBay or Craigs List or at Hamfests or via the various News groups, FaceBook pages and Pinterest!  I myself have quite an investment in Hammarlund, Drake and vintage Yaesu equipment, not to mention a  Homebrew code station built following lines of the late 1930s QST projects.  Yes, I'm in that mix, too.  Which is why I want QSL cards and stationery to reflect that!

I already waxed lyrical over the art and tradition of the QSL card in a prior post.  In this installment, I would like to share what WD4NKA, the Staff and the Management at Paper Wren Press ( which houses WD4NKA!) is planning to do to address the "Vintage Wireless Stationery Void", with any luck and a bit of support - which is to . . .

. . . Offer a humble selection of vintage Letterpress QSL cards!  At a price that may not cover all our costs, but one that is fairly competitive with current prices. Cards that reflect not only your vintage, lovingly restored or meticulously hand built rigs, but also the Era when your fifty to sixty-pound gems were the State of the Art!  

The Project:

In general, I culled about twenty five years of QSL designs from 1919, and on into the War Years.  I identified what I believe to be primary design elements, most of which are pretty obvious.  For one, almost all are either balanced in their appearance by symmetry or by what we called in photography "Rule of Thirds", which balances asymmetry.   Normally the call letters are a pronounced complimentary colour, and more often than not, red.  Basic QSL information corresponds to what most log books of the era called for.  Unless you were an ARRL member and had the "diamond" printed, there were very few extraneous logos tacked on, although there were a few.  Just not enough to rise to the level of standard design.

They looked official.  They did not look like travel post cards like many do today.  They were not glitzy.  They were, in fact, almost spartan, save for the Otto Eppers and Phil Gildersleeve cards that were actually limited edition art cards!  (We are also contemplating an Otto Eppers design, btw.  Maybe Robert Crumb, too!)  

For those who do follow this blog regularly and are unfamiliar with Letterpress, let me share with you a video I made some time ago, showing myself printing a Wedding Announcement:

This second video shows a little about the actual Letterpress itself.  This is actually a short documentary of the Kluge that Nick Sambrata and myself got working at Mama's Sauce printery, Winter Park FL.

Needless to say, these old Iron Horses are amazing animals, and carried the bulk of the printing needs of the Western World for over one hundred years.

The Designs:

Here are the three designs we will be working with Owosso Graphics, Owosso MI, to produce in hardwood mounted copper:

This one is for the NRR folks.  But the design can be modified as a "custom order".  These cards have a pre-printed black shell containing the telegraph key design, title, and qsl info, and the morse code "nrr" that serves as the top and bottom borders.  This card will be standard post card size, 3.5 x 5.5 inches. 

This card is much more traditional, and is largely lifted from about three different pre-depression era QSL cards.  This has the traditional spaces to record your transmitter, receiver, power output and antenna (aerial) data.  This one is for the Dyed in the Wool 1929 "Post Cairo" op who designs his or her rig from the ground up.  Not for sissies!  This card will be standard post card size, 3.5 x 5.5 inches.

This card is more mid- 1930-ish, although examples exist as late as the 1960s.  There has always been a following for this card design, it seems.  My actual examples came from cards that immediately preceded the WW2 ban.  But I have seen these used even when I was a Novice in 1977!  I guess that would mean it's a "timeless" design, for a Timeless Station.  What do you think?

In Summary:

There are a number of QSL printers out there that do great work at a fraction of the prices I am asking.  That is the whole point of modern printing!  To drive down prices, and they do, for sure!  But not without sacrificing that tactile dynamic that can only be made by direct impression of a die or plate against paper.  And engraved plate, or handset metal type produces an effect that two generations have grown up never knowing.  

 

Probably the best way to describe the difference between modern printing and the ancient contact printing modes might to consider a high quality photocopy of a Dollar Bill.  Not that I am suggesting do this, it's illegal.  But if you held that photocopy in one hand and a real dollar bill in the other, you would know instantly which was real.

That's what we're after here.  At about sixty-cents per card for 250 2-colour cards.  $150.00, with a 2-3 week turnaround time. 

 

Well, this is what has been keeping our creative juices flowing at the Print Shop at WD4NKA / Paper Wren Press.  Hoping to hear back from some of you.  Contact me via Face Book or at my email box at wd4nka@aim.com or paperwrenpress@gmail.com.

More will be posted as we make progress with this project. Once again, Wireless meets Letterpress.
 

vy 73, de wd4nka.

Resurrecting the Drake TR-3 and AC-3 Transceiver and Power Supply.(Part 2)

Having finished the AC-3 power supply, and upon being satisfied that it was operating to specifications, it was only natural to try it out.  I already had an idea of what would happen, but I plugged the supply up anyway, attached it to the TR-3 via the big Cinch Jones plug, ramped her up, and voil'a!  

Pop, snap, fizz.  And a mild aroma of ozone filled the air about me.

There is no doubt that the TR-3 was dead.  This must be distinctly understood, or nothing wonderful can come of the story I am going to relate. The relay would not key.  The lights would not illuminate.  Smoke whisked from the audio section.  Various sparks flew from the Vox and Anti-vox potentiometers.  Nary a sound made it's presence known through the headsets.  Not so much as a hum.  The TR-3 was as dead as a door nail.

Mind!  I don't mean to say that I know, of my own knowledge, what there is particularly dead about a door-nail.  I might have been inclined, myself, to regard a stripped cabinet screw as the deadest piece of ironmongery in the trade.  But the wisdom of our ancestors is in the simile; and my unhallowed hands shall not disturb it, or the Country's done for.  You will therefore permit me to repeat, emphatically, that the TR-3 was as dead as a door-nail.

Not being one to follow a straight line, even with coloured pencils and Magic Markers, I set about to do what most geeks like me do when we don't know what else to do: hunt down all the paper, moulded and electrolytic capacitors / condensers, identify their values and replace them.  And to be sure, this is Standard Operating Procedures.  It's not that these capacitor types might be bad, the are bad!  The results were to reveal that such was no more so than it was with the TR-3.

The truth is, there really are not that many to replace!  There are five paper caps and two electrolytics, almost all types the same value.  The papers were replaced by polymer and one orange dip, and the electrolytics were replaced by new electrolytics.

All of these caps are found on small upright phenol boards mounted either near the side of the radio where the control pots and jacks are (Vox, Anti-vox, Meter Zero, Mic, Headphone and Key jacks) - or center rear.  The paper caps are pretty obvious,  they are identical white tubular types, all 0.47 uF save for one, which is .01 uF.  The above photo shows their appearance and the boards they are mounted to...at least, in the early model TR-3s.

The ideal removal tool for these components is a small flush cutter.  The following describes the technique I used to replace them :  I cut them out by cutting their wires as close to the component itself as possible.  This leaves the two original wires soldered into place.  These wires will serve to mount the new component by providing something to solder to without disturbing the original solder.  I found over the years that things go a lot better if you avoid disturbing original terminal solder connects.  That is, if they are good solder connects!

Now, most of these boards can be removed, but go slow. If you can, keep a digital camera that can do micro-zoom handy.  Almost all of the inexpensive digital cameras like the Canon Power Shot will do nicely.  I recommend this because not only are these boards held in place by one or two bracket screws which must be removed, but they are also hard wired to adjoining circuitry at multiple points.  Most of these wires must be cut.  As you cut them, leave them in position so you can re-align them with the wires on the board when you re-install them. 

 

As you can see from this example, the vertical board is held in place by two angle brackets screwed to the chassis, and is also soldered into place by 20-gauge bus wire, plus insulated wire leads.  These insulated wires are not necessarily colour coded, so be observant!  Take good notes, perhaps do a drawing, or best, take a photo.  Digital camera technology is your friend here!  Digital Cameras are part of my restoration tool-box.

 Be sure to photograph, or at least make notes on the wire attachment to each side of these boards!  There will be bus wire cuts, insulated wire cuts and component (resistor/ ceramic disc capacitor) cuts that will need to be re-attached.  I might add that there were two boards whereas I found  I could leave the wires intact, requiring that I simply remove the bracket screws and lift the board a bit.  All I need to do is snip the cap out and have sufficient room to re-solder a replacement component into place.

I wanted to show this photo.  The smoke I mentioned earlier came from this 3.3k half watt resistor which bridges these two component boards.  There was an associated ceramic disc capacitor on the other side of the board, a small bypass cap, that had shorted, creating a path to ground that permitted too much current for this resistor.  In these tube type Drakes, you want to be mindful that they create a lot of heat in confined areas where ventilation is limited.  Many owners will mount muffin fans on the cabinets to force additional air exchange, which isn't a bad idea!

Convention almost implies that we be mindful only of replacing Paper, Moulded and Electrolytic caps. The tendency (and often read written opinion) is to leave the ceramics and silver micas alone.  I say look at everything!  There IS no hallowed component.  They are ALL prone to failure with age.  It doesn't mean you go out replacing all the caps, but don't assume all ceramics and micas are innocent or somehow unaffected by age, time, and heat.  Pay attention to any associated resistors.  A brown or discoloured resistor is your clue to higher currents, which may be due to either a value change in that resistor due to age, or a high current short nearby - normally a cap.  And, beware of strictly going by continuity checks alone.  Most of the shorted caps in my experience showed open continuity on a VOM.  However under high voltages and operating currents, these opens will close!  As such, do not be in a hurry, and keep your variac handy.

 BTW, I replaced that 3.3k resistor three times until I figured out what was going on.

The technique employed here involves the use of Squigs, or "Pig Tails" as we used to call them.  I already made a blog entry about the use of these items.  At one time you could buy them, but these days, I make them from 22 gauge tinned bus.  For details, visit my corresponding blog entry "Resurrecting a Drake TR-3: Pigtails!"

Here is a shot below deck showing the replacement caps having been "squigged" into place utilizing the original wires that were left soldered to their terminal points. You may have to click on the photo to get a good look at these solder connections.  Note the rear boards are not yet bolted down. I was still in the process of squigging their connections back together.

Touching on other things that were going on besides the circuit work, I pulled every tube/ valve, every crystal, one by one and gave them a thorough bath of DeOxit.  You can see the bottle in the photo with the hypodermic cap.  Relays, sockets, any place where metal contacts metal is treated to a liberal dose of DeOxit.

The white metal covers that cover the mA meters and the planetary dial were removed, sanded, repainted with white semi gloss, and replaced.  Possibly a better choice may have been flat white.  But no matter, the blue dial filter (acetate) diffuses any light bouncing around behind the dial.  Make sure there is electrical contact with the slide-on light bulb sockets. Those areas might be best sanded to ensure grounded contact with the bulb holders both for the dial and the mA meters.

Accompanying these activities was the treatment of the cabinet.  The cabinet was awful.  The TR-series Drakes use a clam-shell cabinet which is held in place by twelve machine screws - six for the top, and six for the bottom.

I opted to do the wrinkle finish on the top, and use flat black for the bottom, just to provide an interesting visual break.  I did the same combination when restoring an enlarger, and it was quite attractive!  To read more about how handle wrinkle finish treatments, refer to my prior entry concerning the rebuilding of the AC-3 Power Supply. 

It takes about twenty four hours for the wrinkles to "set" to the point where the cabinet sections can be safely handled. As such, a lot of patience is required. This patience is amply rewarded once the project is completed!  I think Drake should have used Wrinkle Finish too. Again, just my opinion.  I have a lot of those.

Here is another view of the cabinet, under natural light.  All sides wrinkled very nicely owing to the even distribution of heat due in large part to the ventilation holes.

Wrinkle Finish is like a letterpress printed piece.  You have to behold it up close and touch it to really appreciate it.  Wrinkle Finish provides a very robust, tactile surface that engages not only the eyes, but the sense of touch.  This is why I especially like to use it, when appropriate. 

Up to this point we are finished with the circuitry, we finished  the de-oxidation, we finished painting the inside and outside metal work, we also replaced the feet.  What next?  Why....fire her up!

I loaded her into a 60 watt bulb to see if there was anything like output.  And yes!  As it turns out, she is willing to yield about 100 watts cw, and later when I tested her on SSB, about 120-150 watts on voice peaks.  Her finals are old, but are themselves, replacements.  I suspect they were replaced sometime in the 1980s.  I have the originals, where are blown, with cracked glass. 

Here she is, all buttoned up and ready to be parked next to the 2B.  My intention from the start was to use the TR-3 as (gasp!) a cw transmitter!  This was because I had no idea that she would ever speak with a voice again!  She performs marvelously in this capacity!  Flipping her over to cw position, she immediately emits a very weak signal perfect for spotting.  Since this is in transmit mode and the changeover relay is already in transmit position, I can start sending immediately.  When I switch back to the 2B and switch out of the cw position, the spotting signal ceases.  Having grown up with home-brew transmitters and separate receivers and never owning an RF activated ATU in my life, I am used to flipping switches between transmit and receive.  Part of what geeks do!  I did the same with that Gonset shown in the video and one of the photos  which . . . is no longer there as of this writing.  It is now comfy in it's new home at AF4Ks shack.  The Drake is now filling her shoes, and quite nicely so!

A few things still need to be done with the TR-3.  I need to re-wire the filament voltage to the mA meter and dial housing pilot lamps.  The sideband selection switch lights are, however, working fine.  The mic gain is a bit crackly, that will be ultimately replaced. I would like eventually to find a new face plate, too. The TR-3 is, however, dead on frequency.  The power supply is running smoothly.  I do wish to, eventually, replace both mA meters.  It is not uncommon for the d'Arsonval movements to become magnetically gaussed and sticking.  I have to tap the S-meter to break it loose from it's internal magnetic charge.  The rig's mA meter simply isn't working.  All tuning is done using the metering on my Dentron MT-3000A.  But again, I am used to meter-less rigs.  

So, there she is.  But the story isn't over.  What about phone?  

I had thought to let that go.  But curiosity got the best of me.  I did not have the proper plug for the mic jack,  and honestly, I was tired of having to mail order everything.  Our local MilSurp store which used to have bins of these connects had none.  But since I was there, I purchased a 1/4" jack, and retrofitted the original.  Of course, I am keeping the original to replace when the time comes.  But at least I was able to wire up the Shure 444 mic and give her a spin.

And spin it did!  Wow!  ....and talk about great reports!  As of this writing I have worked quite a number of stations under sorry band conditions, all on forty meters, and all say the same thing : the voice "punches" through!  AF4K reports that this TR-3 is a "DX-machine!"   Signal reports aren't bad, either.  As I said, I am seeing 125 - 150 watts on voice peaks.  That's low for these rigs, but the tubes are old, too.  

Hey!  So long as nothing smokes!

The receiver is awesome.  I suspect the passband to be around 2kc.  Upper and lower sideband filters are performing fine.  I might address the carrier null, but it is fine as it is.  Just a wee bit of carrier heard through the HQ-170.

So, there you have it.  The "Resurrection" of a TR-3.  Satisfaction level from 1 - 10: 12.  She is QRO and Go, both SSB and CW.   What about AM?  Well . . . that's for another installment.  My coffee is getting cold.

vy 73 es God bless u es urs!

de wd4nka

(BTW: I published this soon as I was done with only cursory proof reading.  If you find blatant, glaring grammatical or factual errors, check back again.  I proof read these after publication and edit them over time  because, well, that's me, I guess.)

.

Resurrecting the Drake TR-3 and AC-3 Transceiver and Power Supply.

When I was gifted by an elderly ham friend with a few parcels from his ham shack, the focus was on a Kenwood TS-420, a Dentron MS3000A and two Ham-M rotors with control boxes.  Almost incidentally tossed in was a rather neglected, somewhat dirty  Drake TR-3, and not far in the storage area where it was kept (incidentally  NOT where the other items were kept!) I found it's equally dirty power supply, the AC-3.

The storage area was the corner of a garage attached to a mobile home.  You from Florida might have an accurate picture what I mean by that.  No climate control, constant 90-100 degree heat 10 months out of the year, no climate control, and lots of crawly things.  Well . . . it wasn't quite that bad, no crawly things, but the lack of climate control was evident.  This poor Drake probably had not seen air conditioning since the 1980s!

Early Drake radios used a copper clad chassis which looks awesome when new.  Get some age and the copper stains become very evident.  Oxidation is a no-brainer.  Fortunately the chassis are heavy enough to maintain their integrity over the years, in this case, fifty of those years.  I would say this radio was decommissioned and set out to pasture about twenty  to twenty five years ago.  It had been re-tubed sometime in the 1980s, from what I might tell.  The original finals and drivers - in fact ALL the original tubes - were boxed in the boxes of the tubes which replaced them.  You can tell an original Drake valve, or tube: Sylvania.

At some point I decided to attempt to resurrect the AC-3 and the TR-3.  I figured that while I more than likely will not "restore" it, I may be able to resurrect it, for use, perhaps, as a cw transmitter to pair off with my Drake 2B.  It was worth a shot, anyway.

The first object of my attention would be the power supply.  It was an obvious disaster just looking at the electrolytics.  So the first thing I did was search and download any image I could find that might show what the below-deck wiring should at least look like.  Sure enough, Google Images turned up the perfect photo.

I had already determined that this was going to be a rebuild from parts that I either already have, or could easily procure.  There are, of course, rebuild kits for these power supplies, but the AC-3 kit is the most expensive, and requires a bit of body-work to mount.  The manufacture of these kits obviously favour the AC-4 supply, which is a direct bolt-on device with a price tag twenty dollars less!!   If I was going to have to take my tools out, then I'm gonna do it all the way, "Old School" style.  Besides, I had, actually, small hope that this project would actually be successful, but I had to try.

The transformer tested good as far as voltage went.  I expected more from the secondaries at first, but then I recalled that this was an era of Sweep Tubes and voltage doubler supplies.  So, I located a schematic to verify.  (Read: I pulled my TR-4 / AC-4 manual and schematic that I already had. There are essentially no electrical differences between the AC-3 and the AC-4)

Looking over the supply schematic, I noted that the electrolytic filter caps did not show polarity.  This wasn't a problem . . . . until I looked over the negative bias supply.  Then it dawned upon me that I only read about bias supplies, I never actually handled one with my own hands.  I might guess the filter caps have grounded positive terms, but was I missing something?   After a lot of verification I found that indeed they do mount in reverse.   And, if you look closely at the schematic symbol, the caps DO show polarity.  The symbol has two parallel lines, of course, however one is straight, the other is slightly curved.  This is consistent with the traditional printed condenser/ capacitor schematics, historically.  The curved line represents the ground side, in the case of polarized caps.  And indeed, the bias supply caps have the curved line on the top, consistent with the negative bus.  All this may seem logical and inanely elementary.  But I get like that sometimes.  Ever look at a simple word long enough and it starts looking weird?   Like it isn't spellt correctly?  Yeah, as a letterpress printer, that happens to me, too.   

 . . .Sigh . . .

Ok, so I literally gut the whole chassis, remove the transformer, caps, strip it down entirely.  Now, what to do about the caps?  There are five gaping holes in the chassis.  I would like to keep a vestige of the original "look", I already knew this project was not going to be a restoration.  It was going to be a resurrection.

Early in the game, back when I was a Novice, I was in love with gear from the 1920s and 1930s.  And back in the 1970s, there was a lot of it around.  A lot could be had cheaply, too.  Back in the 70s, the big focus was on restoring Victrolas and Gramaphones, not vintage Radios.  I was a lone wolf, or so it seemed. I learnt then that everything looks better in Black Wrinkle Finish!  Yes.  And I still feel that way.  It handles heat better than any other paint (in my humble opinion) and it covers a multiple of ills.  And it looks right crack!  (very nice.  Professional.  Sanitary.  Choose your American adjective.).  

When I first painted this chassis, which had to be done in stages  (one side at a time, and the top separately), the first thoughts of ultimate success - in some manner - began to germinate in my small mind.  Wrinkle finish paint does this, Brethren!!  It inspires success!

You can get Wrinkle Finish at many Automotive supply stores.  I got mine at Auto Zone.  It's not the cheapest can of paint on the block.  Here is my technique:

First, understand that this paint was not intended to be sprayed on primer.  It's a bare metal application.  We used this on exhaust headers back when I did motorcycles, it goes directly on valve covers, and parts that get very, very hot.  You spray it directly on the metal cold, then heat it with a heat gun.  This means that you have to do small areas at a time.  For radio cabinets and chassis, I spray one side well.  Don't spray too thick, but don't spray too thinly.  A generous coating is fine.  I do not mask off the side I am not spraying : overspray isn't a problem.

I take the piece inside the shop and begin to use forced hot air on the spray painted side.  I move the heat gun back and forth, for usually about fifteen minutes, and after a while one corner will begin to wrinkle,  You can see it in the reflected light.  Then that wrinkle will spread across the painted surface to the other side.  It's fun, actually, to watch this phenomena.   You can control areas that have less wrinkle that other areas by focusing the heat on that side.  It takes a bit to develop the touch, but after a while a feel is developed.  After you achieve the level of wrinkle that suites, the process is repeated for another side.  Again, over-spray isn't really a problem because the wrinkle dynamic hides any overlap.  After a while I found that Wrinkle finish painting can be a very intuitive and individual process.  Almost an expression, an art.  Wow.  Making an artistic statement with your transmitter.  Imagine.

In the meantime, I tested the voltages present on the transformer windings.  When I took the AC-3 apart, I tagged all the wires, but good to double check, anyway.  The HV and the LV windings checked at 280 and 125vac respectively.  Both of these windings see voltage doublers with an output of 650 and 250vdc.  The bias supply checked in at 65vac and the filament winding at 10vac.

The caps were all bad and the diodes were questionable.  I replaced them all with 1000v piv silicone diodes, my standard go-to power supply diodes.  As for the caps, I purchased several 100uF/ 450v filter caps.  These were used either singly or in series (in the case of the HV line) with their original equalizing resistors across them.  Since I had these large holes in the chassis which originally facilitated the original wafer sockets which held the above deck filter caps, the decision was made to utilize these holes, as already mentioned. To accomplish this, I used a combination of cardboard tubing painted black, black plastic 35mm film canisters, wrinkle-finish painted pill vials and a hot glue gun..

I began to rebuild the cap that would filter the 650vdc "Hi Voltage" line.  Using a 1.25" diameter cardboard tube, I cut a base from phenal to become the mounting platform for the cap's internal structure.  The photo above gives you a pretty good idea how it came together.

A close-up of the series junction.  The junction between the caps is tapped as a voltage doubler. Black electricians tape cover the two 1-watt resistors.

The wires are all fed through the bottom disk which I just sawed and cut to fit the bottom of the cardboard tube.

Another veiw of the base showing how the wiring is arranged at the bottom.  The red wire is the HV bus, the yellow is for the center tap.  The uninsulated bus is for grounding.

After the tube is slid over the caps, it is sealed to the original wafer that held the original filter cap, with Hot Glue. When the glue cools, the wires are held in position, and when this happens, the series soldered caps in the cardboard tube are braced and held firmly in place.

The larger of the three filter caps is the HV filter cap we just described above.  The smaller two are filters for the LV voltage doubler, only these are housing only one cap.  The covering for these smaller caps are 1.25" diameter pill vials.

The bias supply needed filters too, so we used the remaining two holes on the chassis to mount yet another pair of filter caps.  These were covered by black plastic 35mm film canisters.  The mounting bases are the caps for these canisters. 

Note that I did not paint the rear apron of the chassis?  That was so to preserve the original printing on the rear deck.

I opted for point - to - point hard-wiring, not only to preserve the original "look", but also because this resurrection was going to be accomplished using parts on hand or parts easy to procure.  As it was, I used the original equalizing resistors, I merely supplied all the caps and new terminal strips and diodes.

The re-built caps now mounted, the transformer in place, the wiring under-deck being complete, I now add the rest of the hardware, the bias adjusting pot, and the cabling.  Once finished, another round of voltage checking and smoke testing was undertaken to make sure that the Drake TR-3 had every good chance of having proper operating voltages applied.

. . . and here she is, the completed AC-3 in her new make-over, dressed in wrinkle finish black, sporting new caps, new diodes, fuse and fuse holder, original bias pot, transformer and cables. Total cost to me was under thirty dollars.  Thirty "year 2015" dollars.  Not too bad, I might add.  A decent "junque box", a few runs to the military surplus store (Skycraft, Orlando FL) and a sprinkling of creativity, and she's ready to roll with all voltages checking to manual specification.

Stay tuned for the next installment: Resurrecting the TR-3!

de wd4nka

Resurrecting a Drake TR-3: Pigtails!

This was something I found once in a parts drawer at a TV Repair Shop in Altamonte Springs, Florida back in the early early seventies.  A friend of mine worked there. (His prior job was designing Monsanto's 'Circle Vision' projection screen exhibit at Walt Disney World!  His other love, aside from repairing tube-type TVs was being the projectionist at the Prairie Lake Drive In, right off Hwy 17-92!  Can you dig that?  Einstein with a Soldering Gun.  His name was Jim . . . .)

Where was I? 

Ok. In that parts drawer lay several very small, tightly wound coils of what looked like 22g wire.  They were tinned.  Jim called them "pig-tails".  Their use?  To solder together two pieces of wire, of course!  

I cannot tell you the mountain of frustration I climb whenever I have to get into tight spaces with a soldering gun, and when you mess with point to point wiring in some of these older rigs, you need a hefty soldering pencil.  Why is it that the one thing that has to be pulled is always a multi-point solder in a tight corner that either requires a complete dis-assembly or a very dangerous de-soldering?  You can't get a braid in there, and forget the solder sucker.  I never liked the sucker anyway.  The braid isn't bad . . . but you need a fairly open area.  Both are unwieldy,  IMHO.

TV repair guys were in tight spots all the time.  These little pig-tails saved them a lot of time (and mess).  "Pig-Tails" are not generally available these days, so I began making my own.  I thought I might share how I do these little items, and if you are new to this sort of thing, I'll also include a few shots of an actual repair I made on my last project, the AC-3 power supply rebuild for a Drake TR-3. 

Here goes:

First, I picked up a spool of 22 gauge tinned bus wire.  Next, I went to Hobby Lobby and got a pair of very small double-round needle nose snipes, the kind that florists use to make tight little loops in . . . whatever it is they make tight little loops with . . . 

Holding the wire at the very, very tip of one jaw of the snipe, I twist the wire in such a way as to make a look about the holding "jaw", and then slide that loop up one layer for the next loop.  I always make the loops at the very tip of the snipe jaws to make the smallest possible aperture. If I want a larger diametre hole, then I will wind the looks further down the snipe jaw.

See how the resulting 'pig tail' progresses up as I wind each loop, or "pi"?  You can wind them as long as you wish, and as wide as you wish.  See how the snipe jaws are conical?  The lower you wind, the wider the diametre.  I usually wind mine such that the two wires that I am joining together might have a little overlap room.  When the loop is finished, simply cut it off.  You can also leave a little stub of wire available to hold the pig-tale in place if you are in a tight enough spot.  This can be handy because you have to slide the pigtail over one wire, and guide the other wire through the pig-tail from the other side.  In a tight spot, it might be handy to have a length of pig-tail wire available for a "third hand" jig to hold, leaving both your hands free.  I rarely have to do this, but just an idea.

So,  how do we use a pig-tail?  Well, let's take a look: the above repair was the result of a mis-wired filter cap.  See the limited length of wire I had to work with?  That multi-point solder would have been a disaster to desolder.  Better to keep the original solders . . . if they are good solders . . . alone.  So, in this case, I will pig-tail that length of red insulated wire to that center ground wire from the potted cap you seed there.  (It's not really potted, I made that cap.  It's a re-built paper cap, I use hot-glue to set the bottom and hold the exiting wires in place.  They do not get hot.)  BTW, this is a filter cap for the AC-3 negative bias supply.  I had to flip the polarity, dumb me.

There you go.  The pig-tail you saw on the snipes is being used here.  Pretty obvious what is happening here.  The two wires meet and slightly overlap.  All that is needed is a touch of solder.  Remember, the wire used for the pig-tail is already pre-tinned, so solder flows readily, affecting a very solid connection with a minimum of heat exposure to the surrounding components.  In this case, I will do what Drake always seemed to do:  use very little insulation if buses carrying high voltages are far enough to not be in danger of touching another wire or ground.  Flip over a TR-3 or TR-4 sometime, and look at the sparsity if insulation used!  But then, heck, I remember a time when house wiring was bare, too.  That's why you wanna watch your head when crawling around the attic of a house that was built much before 1940!  Bare wire and stand-off insulators!

Solder applied.  A good solid connect.  The only thing I might add to this narrative is that if you are so inclined, dear reader, you might locate some heat shrink tubing if you have a fear of cross connections with another, nearby bus.  You can find small diametre heat shrink tubing at "Just Radios".  I usually find my replacement caps here, too.  Read their hints and tips page regarding cap replacement!

Just in case you were curious where we were doing this solder connection, let's step back and get a wider panorama.  There it is, upside down AC-3, my "Third Hand" jug, and my 30-watt soldering pencil that dates back to the days of Lafayette Radio Electronics.  Yup, it's about forty years old.  Still kicking.

Ok, gang, that's it!  My little "Tip Of the Day".  Nothing new, but it may be new to some of you.

As I progress on the TR-3 Restoration, I will post here.  There will also be some totally unassociated Letterpress stuff coming up, too.  I have four new dies coming in!

Stay tuned!   de wd4nka.

Update: The "Mini Bandmaster"

I suppose the first thing I should write about is the blue transformer.  Many of you who build audio equipment will recognise it immediately as a power transformer from Edcor.  And you would be spot on.  Two months ago I ordered a 360-0-360v / 440mA power transformer from them to serve as part of a larger power supply for the Mini Bandmaster.  The reason was that I was having a very difficult time getting more than five watts from it.  I was using a much lower current transformer, which I initially figured was the problem.  And to be sure, it was part of the problem, but only a part.  I will explain.

I built this "MOPA" (Master Oscillator Power Amplifier) type xtal controlled transmitter many times over the years, without a hint of problem.  Always with surplus or "junque box" parts.  This project was no different.  The original circuit comes from the 1954 ARRL handbook.

One of the unique features of this circuit was the oscillator output to the 6V6 final.  The author of the original article has the builder utilising a 100uH RF choke to serve both as a Radio Frequency choke, and also to tune the oscillator output to 5 MHz. (hereafter referred to as "Mc".  Hertz rents cars!).   This was to tune the oscillator output to 5mc, which is halfway between 3.7mc and 7.1mc, the then current Novice frequencies.  He states that this provides sufficient input to the final to drive it properly. It is a compromise. This eliminates the need to tune the grid input on the final, reducing the parts count, cost, and complexity of construction and operation for the beginner.  And to be sure, it did, and it does. When it works.

The only problem was that in this case, it didn't.  I purchased two 100uH chokes from my favourite Military Surplus shop down in Orlando (Skycraft Military Surplus), installing one, as per usual.  When the construction was finished, the power output was very low, only five watts.  This rig should do at least fifteen watts.  

I removed the 6V6G, and inserted a 6L6G, only to find the results being the same.  Five, maybe six watts.  The best dip I could get was 60mA on the 6L6G, and 49mA on the 6V6G.  

I rebuilt the pi-output, thinking this was the culprit.  No change.  I concluded that the power supply just did not have the moxy, so I set about rebuilding it with a transformer which I knew could handle whatever was needed.

Here it is, in mid construction.  I figured that I could use this for future projects handling 807s and 6146s, so it was a great investment.  I built the chassis from angle aluminium, which provides a very, very sturdy foundation to build upon, and allowed a space in the center to both mount an octal socket, and feed the transformer wiring through.  It came out nicer than I had allowed myself to hope.

But when it was finished, I realised only a scant increase using either the 6V6 or the 6L6!  This had me going back over the schematic.  What did I forget?  What was that one thing missing?  I went over all my bypasses, all my tolerances, measured all voltages, everything was there and functioning.  WTH??  (What The Heck?....No, the F-bomb will not work it's way into my blog!)

Bry, AF4K, wondered about that 100uH RFC.  I told him I used these all the time, no problem.  He said that he always used a standard 2.5mH RFC, and also had no problems.  So, I pulled it, and stuck a 2.5mH RFC in there.

Wonder of wonders.  10 watts on the 6V6G!!  That 100uH choke was the problem.

The only thing I can think is that these 100uH that I bought were used for something other than RF.  Maybe audio.  I don't know.  But one thing sure: it was the problem!

So, as long as I had the rig open, I thought why not just go all the way and actually place a tuned circuit in there?  The original design concept was to save money and simplify operation, but I figured that since I built this transmitter specifically for use on forty meters, why not optimise it accordingly?  So.....I did.

There went my hopes for simplicity.  But I was glad I had room to make the change without seriously overcrowding things.  Here, you can see on the lower left a coil, wrapped around a 5/8" nylon form, that just happened to snug into a hole in the chassis.  On the lower right, you see a 100pF pilot variable, which again, fit into a convenient hole that already existed.  I only had to drill the two screw holes.  The coil as a computed value of 11uH.  The capacitor peaks the oscillator output at around 45-50pF.  

With the tight spaces getting tighter, I decided to take some parasitic precaution and added a 2.5mH RFC in the 6AG7 cathode line as well.  So now, my simple little Mini Bandmaster has three, count 'em, three RFCs.

That coax you see was problematic.  It added stray capacitance to the output.  It threw tuning off.  I removed it after this photo, replacing it with a single 20g. insulated wire, which the loading cap thinks is just dandy.  

When you build in tight spaces, especially with point to point wiring, be prepared for weird things like this.

So, I buttoned the little "Mini" up, and attached a fifteen watt light bulb to the output, and here is the result:

 

I thought it prudent to make a notation for my own records the changes I made to my "tried and true" little Novice MOPA.  This notation took the form of a revised schematic, which I share below.  A tip of the hat to the RSGB (Radio Society of Great Britain) regarding the schematic style.  These types of schematic stylings were commonly used in their publications of the 1950s and 60s, and I love them.  To me, they are ultra clear and easy to read.

I should add that I do not feel the RFC in the cathode of the oscillator is critical in value.  I would suggest anything from 500uH to 5mH.  If you really want to choke off parasitics, you could also place a 40 - 50 ohm one watt resistor in series just after the amplifier plate pin, winding about five turns of wire around it. This is actually a standard item in most higher power transmitters, but you rarely see it in these little rigs.  But it wouldn't hurt to include it if you have the room. 

So here it is, the completed NRR station project, as seen in the top photo.  I get a clean 15 watts output using the 6V6G, and 20 or more watts using the 6L6G.  The 6V6 dips at 70mA, the 6L6 dips at 90mA.  The signals are very clean.

So far, I have been pleasantly surprised to find that making contacts with this station is easier than I had thought.  The receiver is regenerative, and requires a spotting oscillator to locate the transmit frequency.  This is accomplished by that little box on the right side of the receiver.  It is a 2n2222a xtal colpitts oscillator.  I simply insert the transmitter xtal into it, turn it on, locate the heterodyne on the receiver, then remove the xtal and re-insert it into the transmitter xtal socket.  This places me well within proximity of anyone calling for me, on either side of zero beat.  The swamping of the receiver by the transmitter serves as a sort of "side-tone".  I also use one of the other receivers as a side tone, depending on my mood.  Nice to have choices, no?

This project has been completed for about a week since this writing.  I did use this set-up for NRR in February,  using the prior supply, generating five watts.  I still managed 360 points for NRR, and scored Sweden on 7045.  With all the improvements, I've scored both coasts of the US, a lot of Texas, but after midnight, I am getting calls from Europe!  Really!  Dx on forty meters has been really great lately.  F6HKA reported 559, and OK1FIM reported 579.   Huh.  Fifteen watt Mopa.  Regenerative Receiver.  Really.

This has been a most rewarding project.

I want to give special thanks to WB4WHH for his article, which was actually based upon my original article! His article can be found here.  I helped him with this project over the e-mails originally, several years ago.  I used his improvements on my original design as a guide.  Talk about a serendipity!  We've come full circle, OM!  :)

Well, here we are, the parting shot of the current operating position.  Left to right, Power Supply, Antenna Switch, Mini Bandmaster with SWR bridge atop, Regenerodyne, and spotting oscillator.  The key is a Royal Air Force 8 Amp from 1942, and the headphones are US Military low-Z from the early 1950s.  A Novice Station in 1930s clothing.

Now, all I need to do is print some new QSL cards!!

If anyone has further question, check out the Novice Rig Round Up Facebook Page.  I'll be there.  Also, I can be reached at wd4nka@aim.com.

This station can be heard on the following frequencies usually around midnight EST on: 7035, 7037, 7045, and 7050.

'73, de wd4nka.

The "Mini Band Master".

Before I go too far, I thought first that I would show the dear Reader just what a "Bandmaster" is.  This was an Amateur Radio Short Wave transmitter, which saw production in the mid to late 1950s.  It was built by the then well known Harvey Wells people.  The Band Master in it's essence is a radio telegraph and radio telephone transmitter, the frequency of which is controlled by crystals.  It used, if I recall, a single 807 power tetrode final, capable of about 75 watts input "CW", or "continuous wave", which is sent by hand key.  In other words, International Morse Code.  It was probably realistically capable of about 40 watts output using A3 controlled carrier radio telephony (an AM telephone transmitter).  It was designed for use on the Amateur Radio Service short wave frequencies, between 3.5 mHz, and on up to approximately 29mHz, although I doubt seriously many folks worked these rigs much above the forty meter band.  Power drops considerably with these rigs much higher in frequency.

Many an excited Novice Class license holder used these transmitters, and a fair share of seasoned vets as well.  Many are still on the air today!  Mostly doing code work.  They required an external power supply, and some models came with a VFO, or Variable Frequency Oscillator, expanding the versatility of these black wrinkle-finished boxes.

Were they a "great" transmitter?  Well . . . I thought they were ok when I had one, but the exposed power connections on the back left much to be desired.  Ouch!  But, yes, they were fun.  Eventually we Novices  upgraded to that HT-32 Hallicrafter or that Drake TR3 or that National, (bigger transmitters) and the rest is history.

But oh, these rigs were Iconic.  No other radio looked like the Bandmaster!  They harkened back to the 1930s and 40s with that vertical posture, the black wrinkle finish, and oh, the knobs, knobs, knobs...!  What heart does not melt in the bosom of the wistful Geek just looking at this baby.

Yes, any Op (operator) who's been around the block for a while will know the Harvey Wells TBS-50 Bandmaster at an instant.

*          *          *          *          *          *          *          *          *         *

I went to this year's Orlando Hamcation February last, and came home with what I hoped was a working VTVM (vacuum tube volt meter), which I planned to use to tune up my HQ-170 receiver with.  But when I finally had the time to look it over and fire it up, I discovered that the meter was compromised, requiring a replacement, which is nigh unto impossible.  These VTVMs ceased production sometime in the 1970s, and my particular specimen dated to the mid 1960s.  What to do?

Why . . . what any other red blooded Ham does with a piece of junk!  Build a transmitter inside it!

And that's just what I did.  

Now, rather than go through the blow by blow detail, sufficient to relate that I simply duplicated the last MOPA which I have already described in detail in a prior installment, which used a modified Pierce 6AG7 xtal oscillator to drive a 6V6G in class C amplification mode.  The difference is that this one has Pi output tuning. But when I was done, this former VTVM really reminded my of none other than the Harvey Wells Bandmaster, only in miniature, and with a lot fewer knobs.  What cinched it was when I applied wrinkle finish black paint to the front panel and cabinet!  Oh, my goodness!  I was in love.

Here is a quick Show and Tell of my little "Mini Bandmaster".  This was one of the rigs I used on Novice Rig Round-Up in February.

Building a radio is never a tidy affair with me.  Much less so since my radio shack happens also to be my  Letterpress Shop!  I try to keep my tools over there.... and my wire over here.... my solder gun.... ooops.....over there.  Somewhere in the middle of all this is the object of my attention.

Here are a couple side shots during mid construction.  I just happened to purchase a 0-150mA meter at the Orlando Hamcation, which fit the spot vacated by the damaged meter perfectly.  You can see the Pi tuning variables which I purchased off eBay.  The tuning coil is hand wound around a plastic 35mm film canister, my go-to coil form for MOPAs (Master Oscillator Power Amplifier).  I had just enough room to re-punch the tube socket holes around the existing mini-tube holes.  Because I was able to get away with minimal punching, the chassis integrity remains intact.  That choke you see in the upper photo under-deck is the 2.5 mH RFC (radio frequency choke: helps to keep high frequency signals off the high voltage DC power line powering the tubes.)

The chassis is a simple "L" shaped piece of aluminium which bolts at one side to the front panel, and on the other to the cabinet.  As such, it is held quite rigidly in place.  You can just see the original VTVM front panel beneath the metal sub-chassis here in this mid-wiring photo.

This is a shot below deck.  The variable on the upper left is a 150pF tuning cap, for tuning the output to resonance, and the one on the upper right is a 365 broadcast tuning cap, which tunes the transmission line to the resonant circuit once tuned.  My power receptacle came from a computer power supply.  The wiring is, of course, point to point.  I used bare 22g tinned buss, sliding insulation over it after each piece is cut to length.  For tight spaces, for me, this works better than using pre, or factory-insulated wire.

The rear view.  The rear apron had this convenient wedge cut out of it, so I took advantage of it.  That wedge originally provided a "tongue" of metal to hold a battery for the VTVM.  I cut that off, and utilized the space left by it.

 The top view.  Why are the wires to the mA meter criss-crossed?  Oh . . . because.  Heh, it wasn't until after I hooked it up the first time that I realized that I had the polarity crossed, so I flipped the wire around.  I just didn't re-bend them.  I kinda like it that way, don't you?  No?   Awww.....

Ta-dah!!  There she is, xtal in place.  Code key plugs in front between the tuning knobs.  Lights show DC power (so I can tell the transmitter is on!) and RF output.  With my current power supply (described in an earlier post) I can just squeak 5 watts out of this little rig.  BUT....with the proper power supply it is capable of 25 watts output with the 6V6G, and 40 watts output with a suitable 6L6G.

Aint she pretty?  Yeah, I'm still pretty taken by her.

At first, I wasn't sure if I should put the original brushed aluminium VTVM handle back on the top.  I did, and I liked it so much I left it there.  Maybe somewhat less "Bandmaster-ish", but it sure does lend to that 1930s "portable" look!

For NRR, I paired her with my Regenerodyne receiver, which I converted down to forty meters.  They are quite fascinated with each other, I can tell you.  Oh, and not to be left out, the J-36 keyer, which I also used, along with my RAF 8-amp straight key.

Here is the actual operating position for NRR.  Left to right: Power supply, antenna switch with my little spotting oscillator atop, the "Mini Band Master" (see the light?  I love lights.) and finally the Regenerodyne, which is a regenerative based single conversion superhet of my own design.  The phones (head sets)?  U.S. military, c. 1952.  low impedance. The key shown is the 8-amp'er.

One last shot:  my 33 foot vertical on my roof.  All home made from tubing I had laying around the back yard.  That little five watt transmitter made it across the Mississippi and into Missouri and New Mexico coupled to this antenna.  Also, I worked up into New England!  Keep in mind, five watts, during an event, with solar activity beating the snot out of forty meters.  Not too shabby, methinks.

Well, that's all for now!  Stay tuned for our next installment where some how, some way, in some universe, at least at WD4NKA, Wireless meets . . . eventually . . . Letterpress!!

"And where...", you may ask, "....did that happen here?"

Ahh, yes.  Novice Rig Round-up QSL cards.  But that's another story for another time.

Best 73's!

-gary, wd4nka