Fairbanks-Morse model 8A FOUND! - Videokarma.org TV - Video

holmesuser01 · #1 01-27-2007, 06:03 PM

Was browsing at the Salvation Army today and they had me come to the back room and have a look at what they got today... an F-M 8A from around 1937! Its missing all the knobs, and someone has done a polyurethane restoration on the cabinet.

It's a console version, and I have already downloaded the Riders info for the schematic.

Currently, it is on my variac slowly being brought to life.

I checked the tubes, and found 5 of the 8 tubes to be very weak.

They are:

5Y3G rectifier
6K7G 1st IF
6K7G 3rd IF
6V6 output (metal--original was ST style)
6Q7G detector--cracked-- bet this is what made the thing die!

The 6G5 tuning eye is bright and green on my tester.

Others Good:

6L7G 2nd IF
6C5 (metal, had a G style at one time) Maybe this drives the 6G5 tuning eye?

The 6V6 output got replaced because the 'shorts' light on my tester flickers when I tap the tube. Id like to find G style tubes (ST) for this radio.

Believe it or not, I have spares of all of the bad tubes in this radio. This is what happens when you have been collecting radio parts, etc, for 35+ years!

All of the tubes are of different manufacturers. Anybody know what brands of tubes F-M used from the factory?

Also, since the knobs are all missing, anybody know offhand what style knobs would have been on this unit? All replies are greatly appreciated!

Bruce

Sandy G · #2 01-27-2007, 09:09 PM

Bruce- Would like to see a pic of it as is. I'd bet Mike Koste- Gobs of Knobs could help you...

holmesuser01 · #3 01-27-2007, 09:39 PM

Well....

It powered up fairly well. All tubes are right and good. I got some static at about 75 volts, and slight hum at 100 volts. The tuning eye is dim, but indicates when I get a station. I am getting about 157 volts at the plate of the 6V6GT that I installed. The Riders schematic sez 245 is normal... THEN I starts smelling that good old radio smell of dying electrolytic... I need to replace a 10 mfd 450 volt cap NOW. It got too hot to touch... and this is probably why the B+ is so low.

I plan to replace 14 caps for now that are discolored, etc.

I was gonna take a pic of it, but suddenly my digi-camera wont power up. Aaaraugh!

As for room to install replacement parts under the chassis, I could install 2-3 chassis inside this chassis and still have room left over!

Bruce

Sandy G · #4 01-28-2007, 08:06 AM

Well, sounds like you're in for an afternoon or 2 of Gettin' Intimate w/the Solderin' Iron...but you're gonna have a real nice set on the other side of it...Can't wait to hear how it goes ! Good luck !

ekimetsok · #5 01-30-2007, 01:27 PM

Bruce: I have PM'd you.

holmesuser01 · #6 02-10-2007, 11:26 PM

On Friday, I received 2 20mfd 550v electrolytic caps. Installed them under the chassis, while leaving the originals in place. Turned on the variac and let it cook. After a couple of hours of slowly coming up, I got static, sound, and stations!

I've got to buy more caps, as there is slight distortion in the bass sound. Probably one of the discolored coupling caps near the 6V6GT tube.

Its reasonably sensitive on AM and SW. Police band is quiet, but I have heard things here, too.

I snatched the bakelite knobs off of an RCA radio for now. It really looks nice, too. I still need to get the original styles if possible.

Now, onto the RCA which needs caps, and a big Philco with lots of Loktal tubes that needs caps, too.

holmesuser01 · #7 01-01-2008, 05:57 PM

As promised, here is a pic of the Fairbanks-Morse radio as received.

radiotvnut · #8 01-01-2008, 06:22 PM

That's a fine radio! And, you found it at the SA, of all places! I think the last tube radio I saw at an SA was in the late '90's. It was a beat up early '50's Silvertone console radio/phono combo and they wanted WAAAAAYYYYYYYY too much money for it! All the "thrift" stores around here get greedy when it comes to anything old. The stuff is donated, but, they think it's worth a fortune because it's old and you can forget about getting them to lower the price. Six months later, the stuff is usually still there. I don't go to thrift stores much anymore for that reason. After your nice find, I may have to start again.

holmesuser01 · #9 01-02-2008, 04:02 PM

This radio was aquired last spring. Now, the SA has access to the internet. Their prices have jumped.

Now and then I find things that are inexpensive enough to buy.

I do donate things, too. Several LARGE console stereos this year... all were in working condition and ready to go. I just ran out of room for them.

gary rabbitt · #10 03-08-2008, 04:25 PM

Hi Bruce,

I have a Fairbanks Morse 8A also. I have recapped it and took the time to restuff the original Faibanks Morse branded paper caps, to keep the underside looking original.

If you'd like a photo of the original knobs, let me know. Your cabinet is different than mine, obviously, there were different styles using the 8A chassis. I have an original dealer hang tag I could scan. The speaker is really cool and actually has great sound for this set.

Let me know if I can help you out.
Take care,
Gary

Boobtubeman · #11 03-08-2008, 05:02 PM

Sounds like it uses the same tubes as my DELCO does

Mine uses a 6F6 instead of the 6V6. But i subbed a 6v6 to test mine and it works fine... I went as far as EBAY to find the ST style tubes for it. And i still have the other tubes

Steve

Old1625 · #12 03-09-2008, 09:21 AM

Quote:

Originally Posted by holmesuser01

On Friday, I received 2 20mfd 550v electrolytic caps. Installed them under the chassis, while leaving the originals in place. Turned on the variac and let it cook. After a couple of hours of slowly coming up, I got static, sound, and stations!

I've got to buy more caps, as there is slight distortion in the bass sound. Probably one of the discolored coupling caps near the 6V6GT tube.

Its reasonably sensitive on AM and SW. Police band is quiet, but I have heard things here, too.

I snatched the bakelite knobs off of an RCA radio for now. It really looks nice, too. I still need to get the original styles if possible.

Now, onto the RCA which needs caps, and a big Philco with lots of Loktal tubes that needs caps, too.

Nice score!

Preemptive recapping is indicated on all old radios in original condition; those wax-paper bad boys are usually up to mischief after the set warms up.

The so-called "police band" is usually quiet these days. There is a weather service that broadcasts sometimes just a few KC above the AM broadcast band IIRC, but it's a slop-bucket transmission, meaning you would need to improvise some kind of BFO to copy.

Where did you obtain those 20-550 'lytics?

holmesuser01 · #13 03-10-2008, 11:42 AM

Where did you obtain those 20-550 'lytics?[/QUOTE]

I had to think on this... Smell the burning odor?

I got them through MAT electronics in New Jersey. I'm reasonably sure of this.

Havent done anything else to this radio. I'm using it daily to listen to AirAmerica talk radio, so it gets a good workout.

Thanks for all the interest! Its one of the prettiest radios that I have run across... and YES, I would like to see the original style knobs!

spartanmanor · #14 03-10-2008, 11:49 AM

That's a beauty! Nice find.

gary rabbitt · #15 03-10-2008, 07:47 PM

Quote:

Originally Posted by holmesuser01

Thanks for all the interest! Its one of the prettiest radios that I have run across... and YES, I would like to see the original style knobs!

Hi, I will post some pics of my set ASAP.
I have started with the refinish, but did not like the toning on the trim, it was too dark, and I am in the process of removing that.

A friend gave me the set sayng it needed a good home.