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radiotrope power supply black stuff.....its not tar what is it and how do you remove it?
6/3/2003 7:47:14 PMsean
Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?
6/3/2003 7:50:44 PMsean
Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did

:Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/3/2003 9:31:37 PMNorm Leal
Hi Sean

Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.

Norm

:Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
:
::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/3/2003 9:37:46 PMsean
Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?

:Hi Sean
:
: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
:
:Norm
:
::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
::
:::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 12:55:49 AMNorm Leal
Hi Sean

Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.

Norm

:Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
:
::Hi Sean
::
:: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
::
::Norm
::
:::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
:::
::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 9:25:06 AMTHE PHILCO RESTORER
Hi Guy’s , I can’t figure out what your doing, but if it’s a Tar Box, just put it over a coffee can, open end down and take a plumbers propane torch and go around and around and around it and the tar will melt into the can and what’s inside will to.
PHILCO used 2 types of tar, one low melting and one high melting and I never heat the Bakelite’s just dig it out with a pocket screw driver, out of 200 or so have only broken one


: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
:
: Norm
:
::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
::
:::Hi Sean
:::
::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
:::
:::Norm
:::
::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
::::
:::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 11:20:37 AMsean
Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.

:Hi Sean
:
: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
:
: Norm
:
::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
::
:::Hi Sean
:::
::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
:::
:::Norm
:::
::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
::::
:::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 11:52:12 AMsean
Hello, I noticed that the model 80 has the speaker field getting its power from line voltage. Although my power supply does not have this outlet for the speaker on it, could this be the speaker I need. I do know that my wires from the plates of the 71a tubes go directly to the speaker terminals on the chassis. As noted on the schematic, it would appear there is a "T-3". I dont have a T-3. Is it possable somebody changed the phone wires and added a field coil type speaker?. This is a console with an * inch opening so it has to take some kind of speaker inside. Did they make a high impeadance speaker then....8 inch? If so then maybe I really do have inputs for phono, its just been rewired and used for field coil supply?

:Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.
:
::Hi Sean
::
:: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
::
:: Norm
::
:::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
:::
::::Hi Sean
::::
:::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
::::
::::Norm
::::
:::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
:::::
::::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 12:32:30 PMNorm Leal
Hi Sean

Since wires still go direct to 71A plates try a high impedance speaker. The schematic does show inductance connected between your 71A plates with CT to B+. This inductance has to be in the circuit. Use a modern speaker with output transformer if you don't have a high impedance speaker.

I wouldn't know what someone has done but there isn't a speaker field in US Radio 80. High impedance speakers were available. Even horn speakers are high impedance but I wouldn't suggest using one of these.

Norm

:Hello, I noticed that the model 80 has the speaker field getting its power from line voltage. Although my power supply does not have this outlet for the speaker on it, could this be the speaker I need. I do know that my wires from the plates of the 71a tubes go directly to the speaker terminals on the chassis. As noted on the schematic, it would appear there is a "T-3". I dont have a T-3. Is it possable somebody changed the phone wires and added a field coil type speaker?. This is a console with an * inch opening so it has to take some kind of speaker inside. Did they make a high impeadance speaker then....8 inch? If so then maybe I really do have inputs for phono, its just been rewired and used for field coil supply?
:
::Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.
::
:::Hi Sean
:::
::: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
:::
::: Norm
:::
::::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
::::
:::::Hi Sean
:::::
::::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
:::::
:::::Norm
:::::
::::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
::::::
:::::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 2:57:48 PMSEAN

Hello, If I use an output transformer, how do you suggest to hook up the primary leads? Does the center tap go to B+?

:Hi Sean
:
: Since wires still go direct to 71A plates try a high impedance speaker. The schematic does show inductance connected between your 71A plates with CT to B+. This inductance has to be in the circuit. Use a modern speaker with output transformer if you don't have a high impedance speaker.
:
: I wouldn't know what someone has done but there isn't a speaker field in US Radio 80. High impedance speakers were available. Even horn speakers are high impedance but I wouldn't suggest using one of these.
:
:Norm
:
::Hello, I noticed that the model 80 has the speaker field getting its power from line voltage. Although my power supply does not have this outlet for the speaker on it, could this be the speaker I need. I do know that my wires from the plates of the 71a tubes go directly to the speaker terminals on the chassis. As noted on the schematic, it would appear there is a "T-3". I dont have a T-3. Is it possable somebody changed the phone wires and added a field coil type speaker?. This is a console with an * inch opening so it has to take some kind of speaker inside. Did they make a high impeadance speaker then....8 inch? If so then maybe I really do have inputs for phono, its just been rewired and used for field coil supply?
::
:::Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.
:::
::::Hi Sean
::::
:::: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
::::
:::: Norm
::::
:::::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
:::::
::::::Hi Sean
::::::
:::::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
::::::
::::::Norm
::::::
:::::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
:::::::
::::::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 4:31:55 PMNorm Leal
Sean

Connect one wire from output transformer primary to each 71A plate. Your radio already has an inductor supplying B+ to the plates. If the inductor shown on the schematic is missing then the CT has to go to B+. Connect a modern, low impeadance speaker to the secondary. Your radio should work.

Norm

:
:Hello, If I use an output transformer, how do you suggest to hook up the primary leads? Does the center tap go to B+?
:
::Hi Sean
::
:: Since wires still go direct to 71A plates try a high impedance speaker. The schematic does show inductance connected between your 71A plates with CT to B+. This inductance has to be in the circuit. Use a modern speaker with output transformer if you don't have a high impedance speaker.
::
:: I wouldn't know what someone has done but there isn't a speaker field in US Radio 80. High impedance speakers were available. Even horn speakers are high impedance but I wouldn't suggest using one of these.
::
::Norm
::
:::Hello, I noticed that the model 80 has the speaker field getting its power from line voltage. Although my power supply does not have this outlet for the speaker on it, could this be the speaker I need. I do know that my wires from the plates of the 71a tubes go directly to the speaker terminals on the chassis. As noted on the schematic, it would appear there is a "T-3". I dont have a T-3. Is it possable somebody changed the phone wires and added a field coil type speaker?. This is a console with an * inch opening so it has to take some kind of speaker inside. Did they make a high impeadance speaker then....8 inch? If so then maybe I really do have inputs for phono, its just been rewired and used for field coil supply?
:::
::::Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.
::::
:::::Hi Sean
:::::
::::: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
:::::
::::: Norm
:::::
::::::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
::::::
:::::::Hi Sean
:::::::
::::::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
:::::::
:::::::Norm
:::::::
::::::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
::::::::
:::::::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 8:59:51 PMsean
Hello, could i get away with putting 10uf caps in this tar can? biggest small one I have is .56, next largest one is 10 uf. I have 5 of the 10 uf caps.

:Sean
:
: Connect one wire from output transformer primary to each 71A plate. Your radio already has an inductor supplying B+ to the plates. If the inductor shown on the schematic is missing then the CT has to go to B+. Connect a modern, low impeadance speaker to the secondary. Your radio should work.
:
:Norm
:
::
::Hello, If I use an output transformer, how do you suggest to hook up the primary leads? Does the center tap go to B+?
::
:::Hi Sean
:::
::: Since wires still go direct to 71A plates try a high impedance speaker. The schematic does show inductance connected between your 71A plates with CT to B+. This inductance has to be in the circuit. Use a modern speaker with output transformer if you don't have a high impedance speaker.
:::
::: I wouldn't know what someone has done but there isn't a speaker field in US Radio 80. High impedance speakers were available. Even horn speakers are high impedance but I wouldn't suggest using one of these.
:::
:::Norm
:::
::::Hello, I noticed that the model 80 has the speaker field getting its power from line voltage. Although my power supply does not have this outlet for the speaker on it, could this be the speaker I need. I do know that my wires from the plates of the 71a tubes go directly to the speaker terminals on the chassis. As noted on the schematic, it would appear there is a "T-3". I dont have a T-3. Is it possable somebody changed the phone wires and added a field coil type speaker?. This is a console with an * inch opening so it has to take some kind of speaker inside. Did they make a high impeadance speaker then....8 inch? If so then maybe I really do have inputs for phono, its just been rewired and used for field coil supply?
::::
:::::Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.
:::::
::::::Hi Sean
::::::
:::::: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
::::::
:::::: Norm
::::::
:::::::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
:::::::
::::::::Hi Sean
::::::::
:::::::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
::::::::
::::::::Norm
::::::::
:::::::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
:::::::::
::::::::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 9:38:24 PMNorm Leal
Hi Sean

Most of the time I use 10 mfd @ 450 volts for filters in these older radios. They work and will reduce hum. May increase voltage slightly but not a problem especially in your radio.

Norm

:Hello, could i get away with putting 10uf caps in this tar can? biggest small one I have is .56, next largest one is 10 uf. I have 5 of the 10 uf caps.
:
::Sean
::
:: Connect one wire from output transformer primary to each 71A plate. Your radio already has an inductor supplying B+ to the plates. If the inductor shown on the schematic is missing then the CT has to go to B+. Connect a modern, low impeadance speaker to the secondary. Your radio should work.
::
::Norm
::
:::
:::Hello, If I use an output transformer, how do you suggest to hook up the primary leads? Does the center tap go to B+?
:::
::::Hi Sean
::::
:::: Since wires still go direct to 71A plates try a high impedance speaker. The schematic does show inductance connected between your 71A plates with CT to B+. This inductance has to be in the circuit. Use a modern speaker with output transformer if you don't have a high impedance speaker.
::::
:::: I wouldn't know what someone has done but there isn't a speaker field in US Radio 80. High impedance speakers were available. Even horn speakers are high impedance but I wouldn't suggest using one of these.
::::
::::Norm
::::
:::::Hello, I noticed that the model 80 has the speaker field getting its power from line voltage. Although my power supply does not have this outlet for the speaker on it, could this be the speaker I need. I do know that my wires from the plates of the 71a tubes go directly to the speaker terminals on the chassis. As noted on the schematic, it would appear there is a "T-3". I dont have a T-3. Is it possable somebody changed the phone wires and added a field coil type speaker?. This is a console with an * inch opening so it has to take some kind of speaker inside. Did they make a high impeadance speaker then....8 inch? If so then maybe I really do have inputs for phono, its just been rewired and used for field coil supply?
:::::
::::::Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.
::::::
:::::::Hi Sean
:::::::
::::::: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
:::::::
::::::: Norm
:::::::
::::::::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
::::::::
:::::::::Hi Sean
:::::::::
::::::::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
:::::::::
:::::::::Norm
:::::::::
::::::::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
::::::::::
:::::::::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 9:57:04 PMsean
Hello, there are six caps in the tar can. Do I replace all of them with 10 uf caps? There are 2 on each side of one choke and 4 on the other one.

:Hi Sean
:
: Most of the time I use 10 mfd @ 450 volts for filters in these older radios. They work and will reduce hum. May increase voltage slightly but not a problem especially in your radio.
:
:Norm
:
::Hello, could i get away with putting 10uf caps in this tar can? biggest small one I have is .56, next largest one is 10 uf. I have 5 of the 10 uf caps.
::
:::Sean
:::
::: Connect one wire from output transformer primary to each 71A plate. Your radio already has an inductor supplying B+ to the plates. If the inductor shown on the schematic is missing then the CT has to go to B+. Connect a modern, low impeadance speaker to the secondary. Your radio should work.
:::
:::Norm
:::
::::
::::Hello, If I use an output transformer, how do you suggest to hook up the primary leads? Does the center tap go to B+?
::::
:::::Hi Sean
:::::
::::: Since wires still go direct to 71A plates try a high impedance speaker. The schematic does show inductance connected between your 71A plates with CT to B+. This inductance has to be in the circuit. Use a modern speaker with output transformer if you don't have a high impedance speaker.
:::::
::::: I wouldn't know what someone has done but there isn't a speaker field in US Radio 80. High impedance speakers were available. Even horn speakers are high impedance but I wouldn't suggest using one of these.
:::::
:::::Norm
:::::
::::::Hello, I noticed that the model 80 has the speaker field getting its power from line voltage. Although my power supply does not have this outlet for the speaker on it, could this be the speaker I need. I do know that my wires from the plates of the 71a tubes go directly to the speaker terminals on the chassis. As noted on the schematic, it would appear there is a "T-3". I dont have a T-3. Is it possable somebody changed the phone wires and added a field coil type speaker?. This is a console with an * inch opening so it has to take some kind of speaker inside. Did they make a high impeadance speaker then....8 inch? If so then maybe I really do have inputs for phono, its just been rewired and used for field coil supply?
::::::
:::::::Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.
:::::::
::::::::Hi Sean
::::::::
:::::::: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
::::::::
:::::::: Norm
::::::::
:::::::::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
:::::::::
::::::::::Hi Sean
::::::::::
:::::::::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
::::::::::
::::::::::Norm
::::::::::
:::::::::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
:::::::::::
::::::::::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/5/2003 8:52:22 AMNorm Leal
Sean

Agree, there are 6 shown in the USR&TV 80 schematic. Use 10 mfd @ 450 volts for each. They don't cost much and are small in size. Be sure to get polarity right. Negative on all these caps go to chassis, ground.

Norm

:Hello, there are six caps in the tar can. Do I replace all of them with 10 uf caps? There are 2 on each side of one choke and 4 on the other one.
:
::Hi Sean
::
:: Most of the time I use 10 mfd @ 450 volts for filters in these older radios. They work and will reduce hum. May increase voltage slightly but not a problem especially in your radio.
::
::Norm
::
:::Hello, could i get away with putting 10uf caps in this tar can? biggest small one I have is .56, next largest one is 10 uf. I have 5 of the 10 uf caps.
:::
::::Sean
::::
:::: Connect one wire from output transformer primary to each 71A plate. Your radio already has an inductor supplying B+ to the plates. If the inductor shown on the schematic is missing then the CT has to go to B+. Connect a modern, low impeadance speaker to the secondary. Your radio should work.
::::
::::Norm
::::
:::::
:::::Hello, If I use an output transformer, how do you suggest to hook up the primary leads? Does the center tap go to B+?
:::::
::::::Hi Sean
::::::
:::::: Since wires still go direct to 71A plates try a high impedance speaker. The schematic does show inductance connected between your 71A plates with CT to B+. This inductance has to be in the circuit. Use a modern speaker with output transformer if you don't have a high impedance speaker.
::::::
:::::: I wouldn't know what someone has done but there isn't a speaker field in US Radio 80. High impedance speakers were available. Even horn speakers are high impedance but I wouldn't suggest using one of these.
::::::
::::::Norm
::::::
:::::::Hello, I noticed that the model 80 has the speaker field getting its power from line voltage. Although my power supply does not have this outlet for the speaker on it, could this be the speaker I need. I do know that my wires from the plates of the 71a tubes go directly to the speaker terminals on the chassis. As noted on the schematic, it would appear there is a "T-3". I dont have a T-3. Is it possable somebody changed the phone wires and added a field coil type speaker?. This is a console with an * inch opening so it has to take some kind of speaker inside. Did they make a high impeadance speaker then....8 inch? If so then maybe I really do have inputs for phono, its just been rewired and used for field coil supply?
:::::::
::::::::Hello, Norm you might be right. That would explain why I have two speaker wire terminals that are labeled speaker and the other two are labeled phono. In the schematic the phono wires go to the 227 tube. My Phone terminals just are in the B+ circuit, so I am getting b+ from my field from the phono terminals. I would think phono terminals should go to my 24 being phono gets amplified by the audio stages. Not sure why they would label phono and have b+ on it though. If you dont have anything connected to these phono terminals, the rest of the radio will not get any B+, as what ever is on these terminals is in series with the rest of the radio.
::::::::
:::::::::Hi Sean
:::::::::
::::::::: Inportant - I've been going with the idea your radio requires a speaker with field. This isn't so if you have a US Radio & TV model 80. That radio requires only an old style, high impedance speaker. This would be like RCA 100 series or Atwater Kent E. You could try a modern speaker with output transformer.
:::::::::
::::::::: Norm
:::::::::
::::::::::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
::::::::::
:::::::::::Hi Sean
:::::::::::
::::::::::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
:::::::::::
:::::::::::Norm
:::::::::::
::::::::::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
::::::::::::
:::::::::::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?

6/4/2003 2:34:32 PMDick
I melted pitch from a capacitor bank in Majestic Super B battery eliminator and a AK 30 audio transformer using an electric hot plate. It had to be done outdoors because of the smell.
:Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
:
::Hi Sean
::
:: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
::
::Norm
::
:::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
:::
::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?
6/5/2003 10:30:46 AMTHE PHILCO RESTORER
Hi Dick.
I don't think that's a good Idea, first of all
there is no place for the melted tar to go,and it just gets hoter and hoter and hoter, second
takeing it out of the oven it may spill, and by the time you get it out side it cools, and # 3 it stinks up the oven !!
If you do it over a can, the melted tar just runs out
and do it outside. Have done a lot of PHILCO BIG tar
box's this way


::Hello been looking at this power supply closer and it even has the same color wires as the us 80 does so I just need to replace the caps.......is heating this thing in an oven not a good idea?
::
:::Hi Sean
:::
::: Probably still tar.. Chip away what you can then clean up the rest with paint thinner. It will remove the tar without hurting other things.
:::
:::Norm
:::
::::Hello, I have heard of people having problems with atwater kent power supplys? maybe this is the same material? I know tar flakes off like a candle when you scratch it with your finger nail but this stuff seems more hard, almost like an epoxy but not quite that hard. It did seem to liquify some but it didnt drip off like the philco bakelite tar in those caps did
::::
:::::Hello, I tried heating the black stuff with a heat gun and it doesnt liquify as easily as tar does. I would like to know what it is and how do you get the components out for replacement?



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