Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

1948 Magnavox "Berkeley" Just Acquired!
#1

Greetings everyone, I just picked up yesterday a 1948 Magnavox "Berkeley" Model 134B and the cabinet is in mostly good condition (it has some dings and chips in the Mahogany cabinet) and it has all of the original Ken-Rad branded tubes in the radio (date codes on the tubes are mid 1947 and early 1948 which would be consistent with the radio being a 1948 model year unit) it also has its original 2-speed (33 1/3 and 78 RPM) record changer yet too. 

I need repair the turntable audio cable as the original turntable audio cable was replaced at one point in time and they plugged it into the FM Tuner's audio plug input for some reason. 

I would like to see if I could get the optional FM Tuner Assembly to install in my unit but I'm not sure where or how I would locate one of those.

See pictures below.  

               
#2

I need to replace the power cord for sure and some other stuff on it but I can't seem to figure out how to get the chassis out of the cabinet, there are a couple of machine screws on the back that are accessible from the top side but when I removed them the chassis didn't seem to want to budge, so I checked underneath and sure enough there seems to be 4 bolts underneath but I can't seem to get them loose, plus I'm not sure if this chassis comes out from the front of the cabinet or the back of the cabinet, the way it looks, it looks like it should come out from the front, but I'm not sure.
#3

It appears that the two screws at the back of the chassis are a sort of 'locator' to adjust the face clearance at the front of the cabinet. Once it has been centered the screws (notice the elongated screw cut-outs) would be tightened to hold it in position. The four screws underneath would then be tightened to lock the chassis into position. The four screws underneath are very probably sheet metal threads tightened into pressed screw anchors built into the chassis sides. They mostly rely on friction fit between the threads and the screw anchors. Over the years these can sort of "weld" themselves to each other due to humidity, dirt, and corrosion. I would suggest if they are hex head to use the correct socket (preferably a six-point socket) and a breaker-bar of some sort to apply steady pressure. The screws should break free with a little effort. Once out the works should slide out from the back. Keep us posted on your progress. Take care and BE HEALTHY! Gary

"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
#4

Alright thanks will do. A quick Question, how hard is it to find a FM Tuner Sub-Chassis for this radio? I'm asking because I would love to try and find one and install it inside this radio so I can also listen to FM radio as well on here besides AM and SW.
#5

I got the radio chassis out, the two phillips bit screws on the back of the top side of the chassis had to be removed and then the chassis slid out through the back.  Icon_thumbup Icon_biggrin

The chassis is all original yet, nothing has been changed on it (all original caps and resistors and tubes) and not a spot of rust or corrosion on the chassis anywhere.

The only visible chage/alteration I could see made to the unit was that someone changed out the original record player output plug at some point in time but that's pretty minor in the overall scheme of things. 

I'd love to find an FM tuner Sub-chassis for this radio if at all possible.

See picture below for the radio chassis underside.

   
#6

Place an ad in Wanted Ads for the FM tuner. However, be aware that these are hard to find.
#7

OK, will do.  Icon_thumbup
#8

So I've checked the record changer mechanism, and the motor mounting grommets were dry rotted on this unit and I'm not sure what kind of motor mounting grommets this is supposed to use, does anyone here know what types of motor mounting grommets this record changer uses?
#9

I figured out the type of motor mounting grommets that the changer used and replaced them and it works as intended now.

I just need the correct audio plug for the record changer as the origial one (which was a round 2 prong unit with one prong larger in diameter than the other.)
#10

I have never seen a set so clean on the under side!
#11

I know, neither have I, the set actually works really well yet without a recap surprisingly enough.

I have a feeling that this set was not used much by its original owners (possibly it was just a display piece and only used for special occasions.)

the only issue is that the original phono audio jack (which was a 2-pin paxolin style plug) was replaced with a 4-pin paxolin style plug and then plugged into the "FM" jack (which was a 4-pin paxolin socket) which wouldn't work because the record player wouldn't get any power in FM mode unless you powered it off the "Aux Power Socket" on the back which was specifically for the FM Tuner, so I'm on the hunt for a proper 2-pin paxolin style plug to attach to the record player audio output wire so I can get the record player working on it again.
#12

I'm curious, does this unit utilize a Bias Cell?

I'm asking because I've noticed that there appears to be a Bias Cell Holder (battery holder) underneath this unit, and if so, what kind of battery needs to be installed, and would it hurt this radio to run it without that bias cell installed?

See picture below.


Attached Files Image(s)
   
#13

Not a bias cell holder but it is a ceramic trimmer capacitor. Usually those type are small value of just a few mmfd up to about 45mmfd.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#14

OK, I was just wondering.

This radio is actually working as is without any capacitors being replaced in it, unfortunately the 6J5 tube for the AF Amp stage became microphonic (it was unfortunate because every tube in this radio was original to this radio, I also had to replace the original tuning eye tube because it was so dim that it couldn't be seen anymore, unfortunately the 6U5 tubes are getting kind of expensive now, even though they are the most common of the tuning eye tubes.
#15

6U5 WOW just like filling up my farm tractor.




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Zenith H725
Here's what the inside of AM IFT2 looked like, and the other pic shows the discs I made to take place of the mica and ke...EdHolland — 07:40 PM
Zenith H725
IF2 will need replacement caps. The arcing was severe enough that the mica is pitted and holed where the HT flashed over...EdHolland — 04:04 PM
My Philco 37-116 Restore
Measuring from center tap like the tube voltages show. Cap 127 is isolated from ground. Cap 127 shown in upper left of p...dconant — 08:05 AM
My Philco 37-116 Restore
Are you measuring relative to the centertap or the GND?morzh — 11:57 PM
Philco 610B oscillator wiring
Still not clear on the wiring interface between the 6A7 and oscillator. After refering to the available schematics and s...Tubester — 07:18 PM
Refinishing Ideas
My 37-116 code 121 is the best sounding radio i have...a daily driver. Since we are talking about "changes". ...poulsbobill — 07:18 PM
My Philco 37-116 Restore
Hello, I finally got brave enough to take the cans off the Expander Unit. Got the grid cap wires replaced and back toget...dconant — 06:50 PM
Zenith H725
I got into the first AM IF can today, and found its mica was cracked. Amazing that it was still working. This one makes ...EdHolland — 06:10 PM
Philco model #20
AHH HA , I got it and can’t thank you fellows enough , when I changed the capacitors I took the advice and did not unsol...onlyrick — 02:24 PM
Zenith H725
Hello Ed, yes, I like letting projects run for few days to make sure they don't start acting up . Sincerely Richardradiorich — 01:03 PM

[-]
Who's Online
There are currently no members online.

>