[vecher]

Just recapped the radio.. turned on all tubes light.. but NO audio from speaker... NO HUM NO NOTHING..

What am I missing?

Skip

[morzh]

Skip




Speaker is not plugged in?

On a serious note:

1. Have you checked the speaker, the field coil of it, and the voice coil (conveniently the xfmr is not on the speaker so no unsoldering necessary)
2. The connector at the speaker?
3. The output xfmr?

Have you checked the tubes and their connections ?
Touching the 7C8 grid?

I mean.....there is not much.

[vecher]

YUP Output transformer I thought i checked it before and it was good..No B+ to the 41 tubes..

Philco Part number 32-8120M

Looks like I will be looking for one..

Skip

[morzh]

Skip

Possibly 125 Hammond could do. C or D, I think.

[vecher]

Ok thanks I will look it up

Skip

[unclevinny86]

I used a Hammond P-T125C in my 40-180 and it worked great.

[vecher]

Ok replaced the output transformer.. i now get a load hum from speaker.the loudness changes with the volume.. no other noise and no stations heard..

I do not have the loop antenna attached..Question does it need the loop to work? or will it do something without the loop attached.

Skip

[Radioroslyn]

Wouldn't hurt to hookup the loop.

[morzh]

It should work without any antenna, at least for some stations.
Yes it would remove that question if you connect the loop. Or just a piece of wire to the antenna screw.
If you get loud hum correlating with volume you should investigate it first.
You could try to pass IF signal through....or any signal.

Or keep touching grids, see where it stop.
Or remove tubes, also see where it stops.

[vecher]

Ok Got hold of the loop antenna.. It worked.. was able to receive many stations on AM also some on SW.. However the hum is still there.. not as load and stations cover it up.. but still there.. I tried adding extra filter capacitance.. but no help..

Anything else I CAN TRY TO GET RID OF HUM?

SKIP

[vecher]

(1) Is the hum a constant level regardless of volume control setting... or does it vary with the VC setting?
Constant...

(2) Is the hum very loud or is it just a "background" type noise?
Not real load but annoying

(3) Is the hum a 60Hz tone or a 120 Hz tone?

Seems like 60hz..

Does hum go away with volume turned all the way down? NO Constant hum hum doesn't get loader with volume

Do both #41 tubes have B+ voltage an pin #2? YES 183 volts, 181 volts
Does pin #3 of each #41 tube have voltage? YES 185 volts, 171 volts

Skip