[morzh]

Having finished with the Z Spinet, it's Kirk's Majestic's turn.

Got no sch.
Anyone could point me to it?

The radio seems fairly simple but the sch wouldn't hurt to have handy.

PS. Found on Techpreservation, in DeJaVue format.

[Radioroslyn]

http://www.radiomuseum.org/r/grigsby_gr_...d_151.html

[Arran]

Mike;
 Is it a 15 or a 15B? This looks promising for the model 15:

http://www.nostalgiaair.org/pagesbymodel...043933.pdf

Lets see if the 15B is different:

http://www.nostalgiaair.org/pagesbymodel...043935.pdf

Regards
Arran

[OldRestorer]

FINALLY!
I have been waiting for this one for a year +
I believe it is the 15 Arran. It is the grandfather clock radio they made.

My poor empty cabinet may not even recognize the chassis when they meet again

[morzh]

Terry

Thanks. I am not sure how to download from RM or I would.

Arran,

Thanks also, yes I think this is it. I was looking for #15, it did not occur to me to look for "Chassis 15".

[OldRestorer]

Radio
http://www.radiomuseum.org/r/grigsby_gr_sherwood.html

Schematic
http://www.nostalgiaair.org/pagesbymodel...043933.pdf

[morzh]

OK, it is 15B.

It has that long terminal mount running along the edge of the chassis that 15 does not have.
Which I broke while trying to desolder resistors. Very long, thin and lots of mechanical advantage at that point. Will glue with epoxy.

Finished the recarb today.
Every single resistor has drifted, and those 200K and 300K have gone over 1Meg.
I replaced all but 3 of them.
2K resistor was charred - it was burnng. I hope the RF transformer winding in series survived.

Someone did really ugly recap of the electrolytics. I suspect I know who it is. Don't worry, Kirk, it's our secret and it will die with me.

[OldRestorer]

Not me!
 I did not try to touch this one... I think...
It has been 2 years ya know, 

Make it pretty Michael... 

[morzh]

Came after work, and almost have finished the recap. I took out the capacitor block, it is akin to that in the AK, soldered around the perimeter tin box potted with tar. I decided there was no need to suffer as all the caps are grounded and there are plenty of grounding points, so all 6 caps, some of which looked like solder tabs and some - just wires going inside the box, I soldered to the groubding points and then directly to where the wires that came to the block were coming from. Like the tube panels.
The two that are left are the Y-caps. Shouldn't be too hard.

[morzh]

Finished recap. Rebuilt the speaker cable.

Was tempted to connect the speaker and power up but noticed something strange with the electrolytic capacitors' connection while running a speaker wire to them.
The message to whoever recapped these electrolytics: if I were to power, there would be smoke. And possible explosion. He whoever did that seralized the caps connecting plus to minus. The caps should have their plusses together, not plus and minus.

Anyways. Good news is, the speaker seems to have both the field and transformer intact.
I haven't checked RF coils, there is, as I said before, a possibility of a damage of one in series with 2K resistor, but I hope it survived.

Enough for hoy. The rest va a ser manana.

[Arran]

The speaker filed coil is in series with the negative leg of the power supply, so that would help preserve it somewhat. The tone control is between B+ and chassis ground, better watch that capacitor if it shorts it will destroy the tone control pot. Is there such a thing as a .03 uf 630 vdc safety capacitor that could be used in that spot?
 I'm not surprised about the filter caps being connected incorrectly, but in cases such as these it's usually the negative side that confuses them such as connecting both negative to the chassis and wondering why the set has a roaring hum. Potted condenser cans are sort of a hallmark of Majestic radios, and many others of that era, I don't know what the appeal was, it could have been a perceived ease of assembly, or maybe it was just the fad among engineers at the time, who knows? But it's sure a pain in the bottom now, especially the ones with no terminal board on the bottom and just a bundle of wires sticking out of the tar.
Regards
Arran

[morzh]

Arran

Yes there are safety caps of this and larger value.
With the electrolytics, in this case both positives are together and then the way they are​ now, I think, was a simple overlook rather than intentional. I first thought the same but the grounded cap seems to be wired with minus to the ground so that was not it either. More than two beers during recap?

I am not sure the field coil in the negative preserves anything, the current is the same and in case something shorts out, it still flows through the coil. Safer to touch.....maybe, it is a transformered radio, so it doesn't matter.

Yep, that potted cap is gonna be handed back to Kirk. Like....hmmm.....the operation was a success but somehow we ended up with an extra brain.....well, the patient never made good use of it anyway

[morzh]

It is working now.

Took me awhile to get that bracket back in, that used to hold the electrolytics. I left Kirk's 20uF ones in, though the sch calls for 8uF. Plus I have no suitable low capacitance replacements that would be appropriately current-rated.

One tube is bad, the 51, tested VERY gassy. I temporarily replaced it with a 24 I had. Kirk, see if you have one. I did not risk putting it in, though it did show good conductance, but gave me twice the allowed gas reading.

First it did not want to work. Also the pilot lamp did not light up. The first 24A that transformer is coming to did light up however. So did the 47. The other two 2.5V tubes, a 24A and the 51, did not.
The ohmmeter read good contact along the line.
Came down to the cold spot at the first 24A where the transformer soldered into, the wires could be moved and their tips, that were coming through the solder, also moved. Resoldering fixed it.

After this the radio worked.
I will attempt alignment, maybe tonight. One of the IF transformers is missing an adjustment screw, I don't know if it is expected or not. If yes, will align to the possible extent.

[morzh]

Aligned it by ear. It was pretty much there already. The station (local) seems to be where it should be. Since I have no escutcheon with the pointer I could only tell so accurate.
The radio is similar to a 90 with IF being 175kHz, plus 24A tubes make it even more similar, and so is the alignment, this one has no first RF having the 1st stage as the Det-Osc, so the alignment (to which I had no documents) went with the generator connected to the grid of the 1st Det-osc at IF frequency.

The sound....well, plate detector..no AVC... Should I say more?

Anyway, done with it.
REST!!!!

[OldRestorer]

Already?

Geeze, 
 I hope it was at least a little bit of a pain to restore 

Good work!