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Philco 84 continuation
#1

Hello Everyone,

I am once again back on trying to restore my Philco 84. I had stoped working on it for a few different reasons which hurt me because some of the knowledge I picked up on theory
went down the drain. Here's what I did am where I am at:

I replaced all the resistors except a wire wound 325 ohm which still measured at that value.
I replaced the bakelite capacitors and replaced the 8k & 4k electrolytic capacitors with singe 10k/10k electrolytic capacitor .
I added a S7 speaker from a Philco 60 because mine was to far gone to try and repair (I tried).

When I powered it up I just got noise out of the speaker with nothing really appearing different as I changed frequencies. I read that filter capacitors
sometimes cause this problem but electrolytics seem good and I made sure that the rivet on the 42 tube had a good ground which was completed by a 
previous owner.
I made continuity measurements on the coils and they seem in range. I know I should replace the 16k resistor with a higher wattage one.

Are there any suggestions on what I should do next on troubleshooting? I do have an oscilloscope and a older signal generator. What areas do you
think I should test. All the vacuum tubes are lit and tested fine on my tube tester. I have attached some pictures and the schematic.

Regards,
Bob


Attached Files Image(s)
           
#2

Hello Bob,
First of all those electrolytic capacitors are 4 and 8 ufd not 4k and 8k ?
So what is in not doing far as the set goes when you tried it?
also Did you double check your work ?

Sincerely Richard
#3

Hello Richard,

I used a single can w/ 2-10 uf capacitors. Sorry about the 10k. I am rechecking my wiring and soldering.

Thanks for the observation and reply.

Bob
#4

hello Bob,
yes, just trying to "dot the i's and cross the t's"if you know what I mean?

Sincerely Richard
#5

Hi Bob, Just making sure, do you have an antenna hooked up? My 84 does not receive anything unless I have a long wire antenna hooked to it. Don't forget to add a fuse.
#6

Hello Richard,
Thanks!
#7

Hello,

I just connected an insulated piece of wire inside the house. When I move the frequency selector it doesn't seem like the noise really changes. What size fuse would you select? Thanks for your input,

Bob
#8

I did a 1 amp slow blow in mine.
#9

Some things to check if you have not already done so.

1) Continuity of the antenna transformer and IF transformer coils.
2) How did alignment go? can you hear the modulated tone during alignment?
https://philcoradio.com/library/index.ph...ers-vol-i/




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