Greetings to All
The light at the end of end of the long tunnel is getting brighter every day. I hope everyone is doing well. Many of us are beginning to feel a little safer and more relaxed as more people get vaccinated.
We are having good attendance at the shop on Tuesdays & Saturdays, even though we still comply with the mast ordinance. Some days all of our shop work stations are busy.
We are getting weekly calls from individuals from several states interested in the Society. Some wish to make donations of radios & equipment, while others are looking for someone to repair a radio heirloom or plan a visit to the museum or the Shop.
Recently, member Marvin Moss from Georgia donated 28 “banker boxes” of various radio and electronic related items. As members go through these boxes, many items are being incorporated into the Society’s parts department, the permanent radio displays or the shop inventory. The remaining items will be made available to members, either by direct purchase or as part of a future auction. Some items may be held for sale at a future hamfest.
,We recently received a call from a lady in Mississippi who wished to donated her father’s entire radio collection. She sent several impressive photographs of this large and valuable collection, which included many cathedrals, tombstones and console radios. All of the radios appear is excellent condition. We believe her father was a former member of the Mississippi Antique Radio Society. Plans are underway to pick-up and deliver this collection to our shop.
Many of you may not know we were able to purchase some museum quality radios from the family of Society member, Marvin Shepherd. Marvin was the Society’s consummate expert in every area of radio restoration, From the electronics to cabinet restoration, Marvin was a “miracle worker”. He developed creative solutions to every restoration nightmare and always cheerfully shares his vast knowledge and techniques with other members. Much of this purchase will be added to our permanent collection. I want to say thanks to all who have helped arrange the purchase of this wonderful collection.
If you have not been to the shop in a while, please consider coming back. Masks are still required in the building per Alabama Power requirements. We hope this requirement will change soon and we can fully open the shop and museum. We will keep you advised.
That’s all for now. See you at the shop, as soon as possible.
Quote of the Month
Eat a live toad the first each morning.... and that will be the worst thing you'll have to face all day.
Ton Desaulniers, AHRS Member
What was that again?
Submitted by Tom Desaulniers
Bzzzzz, hissss, crackle. What the heck is that noise? None of the other radios in the shop are making that noise. Hmmm. Turn off the fluorescent lights for a minute. Nope. That didn’t help.
Where in the world is that noise coming from???
That was back in 1966 when I was working my way through college at the University of Alabama in Kincaid TV Sales and Repair.
Someone had brought in a 5-tube AM radio with complaints of noise. Hmmm. No kidding.
All the tubes were OK and even swapped them temporarily for new ones. No good there. OK, take it out of the cabinet and pull the schematic for it. All the plate voltages were Ok, and nothing looked burned or distorted. So I started eliminating stages by “shorting” the signal to ground with a .1 mfd cap. The noise went away when the volume control was turned down, so that eliminated the first AF amp and the output circuit.
Checking the grid voltages showed at least where the problem was but still not WHY. Finally I decided it had to be a bad IF transformer, so I got one from stock (that was back in the happy days when there was a room full of useable and marked parts). Sure enough, it started playing perfectly with the new IF “can.” Great. Happy customer and happy boss!
That went into the VERY FAR reaches of my fading memory for 56 years. Never even once thought about it again.
Until 2021, that is, when I got two radios from the AHRS auction. And low and behold, BOTH of them presented me with the old static problem. But at least this time I had a good idea where to look for the trouble. Sure enough, grid voltage on the IF amp tube was jumping up and down like a rubber ball. All well and good, but now, 56 years later, where in the world can I get a new one???
I took the IF can out and checked the coil continuity on the input and output windings. Hmmm. About 20 ohms. Seems right. I decided to drag out my old trusty Heathkit capacitor checker and check between windings for leakage. OK at 25 volts, but at 100 volts, it showed shorted or at least badly leaky.
At this point I had nothing to lose so I took the can apart and drilled out the rivet holding the bottom of the socket apart. There I found a ¾-inch square of mica with silver plated pads. And upon closer inspection I could see black and darkened tracks from one pad to the other. Well, there was my leak.
I had to take a guess based on looking at some other old radio schematics and decided about 100 pf would do. Using my brain surgeon skills, I carefully bent the pins out of the way and soldered some 100 pf caps I found in my junk parts. When I got it all back together it worked great except, I had to unscrew the adjustments several turns to get it tuned. I suppose my guess of 100 pf should have been maybe 80 pf.
Well, anyway, from the attached pictures you can see the string of events I took to get it fixed and repaired. And the picture of the piece of mica clearly shows the black tracking where it should not be.
I found a place up in Illinois called Bi-State Vintage Radio Repair (firstname.lastname@example.org). I called and spoke to a nice man named Gary and told him of my IF can story. He laughed and said I had encountered “SILVER MICA DISEASE,” which was the first time for me ever hearing than name. He even sent me a good can for 10 bucks. What a deal!!
Anyway, it seems that this is a pretty common problem in the older radios. Well, they’re all old now but in the 60s that hadn’t had time to develop into a common problem. I’m certainly not a physicist or anything, but my guess is that somehow, due to voltage differences, the silver gets plated or creeps across the gap between the plated pads. It may be helped in the process by humidity or dust getting inside. Who knows?
So that’s my story and I’m sticking to it. But first, take a picture of the wiring before you ever remove that IF can.
Tom Desaulniers / K4VIZ / Conway, Arkansas
Formerly of Leeds, Alabama
Recent Large Donation to the Society
Member Marvin Moss, from Georgia, just made a large donation of 28 banker boxes of various electronic parts and pieces.
Photographs by Dee Haynes
More Happenings at AHRS
Chris Hutto & Stephen Musch working on a radio problem
(Photograph by Tom Killian)
“Wag” Waguespack, Dave Johnson & Frank Parker
(Photograph by Tom Killian)
Regular Saturday meetings have been suspended due to the coronavirus, however a few members are coming in on Saturday to help maintain the shop and equipment. Masks are mandatory.
We meet every Saturday (unless a Holiday weekend) at 9:00 a.m., at the one-story AHRS Shop at the corner of 8th Avenue North and 18th Street, (1801 8th Avenue North, Birmingham, AL 35203). Birmingham, AL 35203). Use the rear (Southeast) entrance.
Regular Tuesday workshops have been suspended due to the coronavirus, however a few members are coming in to help maintain the shop and equipment. Masks are mandatory.
The Shop is open on Tuesdays at 9:00 a.m. until around 11:30 a.m. Note that parking can be a problem on Tuesdays, so you may have to find street parking occasionally.
Regular meetings have been suspended due to the coronavirus.
We meet on the fourth Monday night of each month, too, at 7:00 p.m. Please come join us!
The electronics classes have moved to “Zoom”. Check your emails for schedule and How to participate.
One more great benefit from becoming a member of AHRS--free Electronic classes!
Classes are taught the first Saturday of each month (except when something special is taking place, then we agree on what Saturday).
We start from the beginning Ohms Law, inductors, resistor and Capacitors color codes, as well as what each component does within the radio circuits. We also teach how to use test equipment used in the repairing of radios. We teach troubleshooting radio troubles, as well as how to read a radio diagram. There are coil winding classes, and one-on-one repair help. Come join these classes!
Membership dues are $25 a year, payable beginning in January. If you have questions about your dues, you can contact Treasurer Mike Woodruff at 205-823-7204. Dues can be mailed to AHRS at P.O. Box 131418, Birmingham AL 35213.
Be sure and check out our website at https/www.alabamahistoricalradiosociety.org, which has copies of all newsletters from 2006 to the present (click on News), videos, photo galleries, museum, Old Time Radio columns, Projects, Reading Rooms, Archives, and Contact Information
President – Dave Johnson
Vice President – Steven Westbrook
Recording Secretary – Richard, “Wag”, Waquespack
Treasurer – Mike Woodruff
Boyd Bailey, member and Instructor 334 412-6996
Website – David Lake
Newsletter – Jim Rogers