[RodB]

Nice job on the battery, Bob. Can the box be opened to replace the 9 volters?

[klondike98]

Yes, I plan to put a Velcro closer on the top.

[radiorich]

Hello Bob,
That battery looks great nice job !

Sincerely Richard

[MrFixr55]

Dittos, sweet b on the battery. Love the "9 Lives" logo, remembered from my childhood. Other neat ones are the Bright Star, Burgess logos and the transmitter antenna with sparks used on the Eveready B and C batteries.

[radiorich]

hello mr Fixr,
for sure !!
I have some radios that I need to make some batteries for too.
Sincerely richard

[sam]

bob 
Nice work on battery . If you don't. Have terminals i have a few spares 

Sam

[klondike98]

Thanks Sam. I'll let you know. I can probably scare some up from the local radio club.

[Paul Philco322]

Haven't thought of Burgess batteries in a while Mr. Fixer. Boston Edison always used Burgess in their Bright Star yellow flashlights. My dad sometimes brought home a few spares, ahem......Paul

[Vlad95]

Haven't thought of Burgess batteres in a while


 [Image: https://www.radionostalgia.ca/lib/Images...gess1D.jpg]i



[Image: https://www.radionostalgia.ca/lib/Images...s-XX45.jpg]

[klondike98]

I've started looking into the very weak and garbled reception in the set (I have the HS-62A version of the chassis seen in the schematic). Powering up on batteries for this set did not change the poor reception so I injected an RF modulated signal onto the grid (pin 6) of the 1R5 and checked to see what I got out at the plate (pin 2). I have a vintage Lafayette KT-208 signal generator and tracer. The tracer probe picked up the modulated tone applied to the grid but nothing at the plate (well there was a motorboating sound but it was not the modulation frequency). I took the 1R5 out and replaced it with another but got the same result. Both tubes check ok on my Jackson 648R tester.

My voltage around the 1R5 are:
Pin 6 67volts
Pin 3 37 volts
Pin 4 -3 volts
Pin 7 1.2 volts

R2 measures right at 103k ohms and pin 3 of IR5 to pin 2 of T-1 is dead on 22k ohms.
I've cleaned the tube pins and socket and do not see any misconnections. I'm thinking I must have a problem in the L-2 oscillator coil or T-1 IF transformer, neither of which is good news I think. Time to think about things...

[Image: https://www.dropbox.com/scl/fi/06vp7t5yx...4jl3&raw=1]

[Arran]

Bob;
I was just thinking that maybe the 1R5 tube doesn't like being operated at 1.2 volts on the filament, though you did mention running the set from batteries with the same result. From what I remember 1R5 tubes can be quite particular about voltages on the plate and filament, 1/10th of a volt too low and they won't oscillate, though the set is getting reception so it must be oscillating. Have you compared the service info between the Motorola and the Roger-Majestic, and the Phillips versions? I'm kind of wondering why the Phillips used a 150 ohm resistor verses a 160 ohm in the Motorola after the selenium rectifier? Was there a problem with the larger value?
One more thing to check, what about the loop antenna in the lid, is there good continuity? Are the leads connecting it good with good solder joints? It sounds too obvious but I've noticed AC/DC radios play poorly with one end of the loop antenna open, weak reception, with garbled audio sometimes. This thread makes me want to get into the set I have, though I probably should not.
Regards
Arran

[klondike98]

Thx Arran, I will check the antenna connections. Right now the loop is alligator clip connected to the chassis since you can’t access anything for measurement with the chassis buttoned up in the cabinet. Those connectors might be dicey.

[Vlad95]

Bob, this is the wrong sequence to look for problems and setup circuits.
Always start checking the signal path from the end of the circuit.
1) Connect the audio signal 400-1000 Hz to the first grid of the power amplifier - 3S4. Normal sound level in the speaker should be with an input signal level of 0.1-0.5 V
2) Connect the audio signal to the first grid of the amplifier of the first tube - 1S5. Normal sound level in the speaker should be with a signal level of 0.01-0.1 V
(Make the connection through a capacitor 0.1-0.01 nF)
If the audio part works correctly, go to the IF. Connect the signal generator to the radio through a capacitor 100-1000 pF
3) Connect the IF signal 455 (or other according to the specification of your radio) to the IF plate of the tube - 3U4. The normal sound level in the speaker should be with a signal level of 0.01-0.1 V
4) Connect the IF signal to the grid of the IF tube - 1U4. The normal sound level in the speaker should be with a signal level of 0.5 mV-5 mV (or better)
Try to adjust the IF filter T2 to the maximum signal
5) Connect the IF signal to the plate of the first tube - 1R5. The normal sound level in the speaker should be with a signal level of 0.5 mV-5 mV
Try to adjust the IF filter T1 to the maximum signal
6) Connect the IF signal to the grid of the first tube - 1R5. The normal sound level in the speaker should be with a signal level of 0.1 mV-1 mV (or better)
Try to re-adjust the IF filter T1 and T2 to the maximum signal.

And only after these 6 steps you can try to check the correct operation of the RF, adjust the RF settings and check the correct operation of the oscillator.

[Arran]

Vlad;
I would tend to agree, I only suggested the loop antenna connections since he was already looking at the end of the radio. I would also suggest looking at the plate load resistor on the 1S5 tube, those can go up in value, if not go open circuit, the grid bias resistor on the 3S4 is another weak point. I was certain he mentioned checking them before, but sometimes components behave differently after voltage is applied, carbon composition resistors are notorious for this.
Regards
Arran

[Vlad95]

I just bought on e-bay very similare radio - "Motorola 5M2U", just from 1950, not 1948 as here.
Pice - $10  (but shipping $25   )