[morzh]

OK, seem to find one in Renovated Radios.

Part GPH-RFTR

http://www.renovatedradios.com/parts.html

Can someone confirm this is it?

[vinzer]

That's the one I used on my 38-116 should be the right one.

[morzh]

yeah I bough a couple today in the morning, spoke to the guy he said those should fit and if they don't he will refund me everything. They are cheap so not too risky.

Its sizes don't make sense - the lesser diameter is equal to the hole diameter and he agreed this is not right, hopefully he will correct it.


Thanks.

[morzh]

Powered up with isolation xfmr and variac. No load, no tubes - just transformer voltages.
I don't care about the values - they simply should make sense.
All seem to be good so far - all filament voltages are present, the voltage between the rectifier's anodes is good and rises fast when you turn the variac.

OK, now after I confirm there is no shorts to the DC load I have to bring the speaker.
God help me!

[Radioroslyn]

Good job Mike,
Want the hear that puppy sing!!!!
Terry

[morzh]

Thanx Terry.

Check the rectifier, all fine, then connected the speaker - the voltage did not appear on the output....found a broken wire, the one connecting the minus of the first two electrolytics to the other two and to the field coil....old, rigid...broke.
Well, I had two beers and it is late...coupled with high voltages this is a bad combination so will proceed tomorrow.

Nitie-nite y'all!

[morzh]

OK, proceeding.
Restored the wire, got the voltages.
Populated the output, the driver and the 1st audio.
Got a bit scared of large voltages while measuring output.
Then I lowered the Variac, waited about 30 sec, touched the wiper of the volume and got the buzz.
Releazed the wiper, heard the noise.
Nice.

Then I realized that I have 1kOhm/V meter.
Believe it or not...NO DIFFERENCE!!!! DMM (FLUKE 189) or my MX-815 B/U...within the tolerance both show the same.

Now, I put the voltage to 110V, waited 'till the noise appeared...all voltages then fell exactly in the range shown in the chart. 290V at the output, 225V at the driver. Again, no difference when using DMM or 1kOhm/V meter.

Then again, 1kOhm/V at the 500V scale makes it 500 kOhm load which is fairly small, 0.5mA at these voltages.

So I guess for big radios where the currents are large, especially at the audio stage where there are no resistors in series with B+, it does not matter what one uses for measurements.

OK, so WE ARE BUZZING AND HISSING!!!
Nice.

[morzh]

OK,

So I figured if it hisses and buzzes, it probably seeing some RF, so I simply switched it to the left-most which I figured would be Broadcast and, without any antenna (I have a strong local that all my radios see without any aerial) turned the gagng.....boy did it sing! Nice, clean, loud. The selectivity is very sharp. You can barely turn the shaft and the station's gone.

I am still not sure how antenna is connected. There are two inputs and they look symmetrical. Does anyone know exactly how the antenna is connected to the real panel's terminal?

Magnetic tuning also seems to function.

And I did not even replace the output 6A5 tubes which I bought, but I figured the old ones should work, and if they do (which seems to be the case), I will retain the new ones as replacements.

Woo-hoo!

Now it is remains to be seen how it sounds when put in the cabinet in the evening when the real music is broadcast.

[Radioroslyn]

Well Mike it's almost time to sit down and relax in a comfortable easy chair next to your 37-116. These set can make an AM station sound like FM because of the wide bandwidth. That's what the treble control will do. Short of a lighting storm they sound great!!
Enjoy it tonight!!!
Terry

[morzh]

Almost....I won't be able to bring the cabinet upstairs by myself and not damage anything around, so I will wait a little before I put it in.
There's yet bunch of things to do, I have to see how the rest of the bands work, alignment, then assemble back the auto-dial, I have light socket which is bad (I hope that's the only one), so I will listen to it outside the box tonight.

[Radioroslyn]

So does Mrs. Mike like it??
Terry

[morzh]

Mrs. Mike so far has kept out of it.
Then again at this point it is a mere chassis with some wires sticking out of it, so there's nothing to appeal to women's sense of aesthetics....let's see when it is all dopned.
Though I kinda doubt she will be enchanted....but she does not mind me having fun, and this is what counts.

We are looking to expand soon, so it is quite likely I wil'l have more space for my toys.....

[morzh]

Used a short piece of wire for an antenna, and had quite a goodly number of SW Foreign Broadcast stations pulled, very loud.

OK, maybe it's time to re-assemble the dial and start alignment. Need the dial assembled for that.

The middle band I guess is the police, right? As in all my other radios with it, loud hum at the leftmost and nothinfg much on the right side of the scale. Normal, I guess.

[morzh]

Question: antenna hookup.

The input circuit looks like it want some sort of a closed loop thing, either a frame or a dipole, connected to both "red/black" terminals.
So, if only connecting 1 wire, should I then connect the GND jumper to the terminal 4 (the center points of the input coils)?

[morzh]

Currently...