46-1203 code 125 restoration
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Hello
I just did a recap on a 46-1203. The volume seems to lower as the set gets hotter. I have also replaced the 35l6gt and the 50x6. The only different electrolytic I used are the 250v 22uf in place of the 15uf but I dont think that is my issue.
Thank you
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You could start by taking voltage measurements of the tube pins before then after the set warms up and volume drops. Leave the volume control at the same level for all measurements. Compare them with the chart in the schematics. That should show you what stage to look at. Tubes and resistors are heat sensitive and are generally the first suspects. Also consider that four of the tubes are loctals and need to have clean pin connections otherwise they cause strange problems. Be sure the B- common is not at chassis ground. You are fine with the 22mfd in place of the 15.
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RodB Wrote: Also consider that four of the tubes are loctals and need to have clean pin connections otherwise they cause strange problems.
I will second that. For decades I have kept 1mm, 2mm, and 3mm microswabs on hand for cleaning socket contacts - they are sold to beauticians on Amazon. 1mm microswabs and DeoxIT D5 are my choice for cleaning loctal socket contacts.
Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA
https://plymouthcolony.net/starcity/radios/
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Thank you all very much. As an update the c102 popped. It got very hot and I am not sure what caused that. I will clean all the tube contacts and see what happens.
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Double check that the polarity on all those electrolytic are correct.
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The power supply appears to be a voltage doubler. For this supply to operate correctly low ESR caps should be used and at equal values given. The caps will heat if not low E and voltage/hum will be off if MF values not equal. If not 15's then 22mf "should" be O.K.
Sorry, can't find "c102" for any further advice I am referencing Riders at Nostalgia Air for a schematic.
Do check for leakage from C22 on 35L6 pin 5 control grid.
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
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Chas, C102 is one of the 15mF caps you were referring to in the power supply (it shows as C15 in the Riders schematic). The numbering is from the Philco Service info found in our library at:
https://philcoradio.com/library/download...6-1947.pdf
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You should supply a link or copy of the schematic you're using. I can't find a C102 on the one I'm using. Don't apply power until you determine why that cap blew. It was either installed backwards or there was too much voltage on it.
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Quote:Chas, C102 is one of the 15mF caps you were referring to in the power supply (it shows as C15 in the Riders schematic). The numbering is from the Philco Service info found in our library at:
https://philcoradio.com/library/download...6-1947.pdf
No probs, same difference
Then the ruptured cap is one of two that require "special" attention as I noted above.
I found these as a descriptive but quantity of 10 may be too many.
Do check the voltage requirement I am only estimating, 350volts may be a better caution
https://www.amazon.com/Fielect-Electroly...B081ZJCHX5
Chas
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
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Thank you all so much. Iwas a victim of some else worked on this and put one of the caps on backwards my bad for not checking the schematic as I was replacing the caps. Amp seem to be working fine except get a squeal at high volume. I will continue checking and again thank you all for your help.
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hello,
Of the two speaker wires one is blue the other is a white striped. What wire is the positive ? There is also a black spot on the speaker where I assume the negative is connected.
The set play's fine but lacks any bass at all. I just want to make sure It's hooked up correctly.
Thank you.
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I merged your speaker wire question with your original 46-1203 thread. Please keep all the electrical restoration questions for your 46-1203 in the same thread. It helps keep continuity with the restoration, helps future people find information of value in their restorations and we ask that you do this in the rules. Thanks.
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Thank you. Next time I'll keep it on the same post.
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I was sweating through my repairs. Found someone had connected a capacitor in parallel with another. They thought where the lines crossed on the schematic it was connected. Ever since I've been checking anything that looks newer than the original.
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