Hello All,
This set is from 1972. I hope it's not too new for this forum. I am getting a very loud ear piercing tone from the speakers on AM. If I touch one of the speaker wires, it gets louder. If anyone has any ideas what could cause this problem, please help. Also, the volume is not as loud as it should be. Both AM and FM work.

Thanks,

Dave...

Which wire is which for the speakers?:

Orange with stripe?
Pink with blue tracer?
Pink with grey tracer?
Ivory?
Black with white stripe: Speaker common.

No matter how I hook up the wires, the fader fades from left to right instead of front to rear. Maybe the output capacitors are defective.

Hi again Dave,

Glad you got the Buick radio going.

On these solid state car radios, the piercing tone is usually caused by an open filter capacitor. My 72 Ford/Bendix manual seems to be missing, so all I can offer is from the 71 manual. The filter capacitor is a 3 section can soldered directly to the circuit board. 2-400mfd. sections, and a 1000mfd section. Looking at the printed circuit side of the board, starting at "12-o-clock" on the capacitor, section "C" is 400mfd. 4 o-clock is section "A" 1000mfd. 8 o-clock is section "B" 400mfd. Your 72 may be different.

Sorry I can't help you with the speaker wiring, the 71 manual shows only 3 speaker wires leaving the radio. Orange is left audio, white is right audio, and violet is ground (speaker common). Audio comes directly from the output auto-formers, no output capacitors.

Meade

:Hello All,
: This set is from 1972. I hope it's not too new for this forum. I am getting a very loud ear piercing tone from the speakers on AM. If I touch one of the speaker wires, it gets louder. If anyone has any ideas what could cause this problem, please help. Also, the volume is not as loud as it should be. Both AM and FM work.
:
:Thanks,
:
:Dave...
:
:Which wire is which for the speakers?:
:
:Orange with stripe?
:Pink with blue tracer?
:Pink with grey tracer?
:Ivory?
:Black with white stripe: Speaker common.
:
:
:No matter how I hook up the wires, the fader fades from left to right instead of front to rear. Maybe the output capacitors are defective.

Meade,
I thought it was something like that. This set's PC boards are so jammed in, it's hard to find anything. The FM and front end board is screwed to the back. There is a top board with AM circutry and tuning mechanism, and a bottom board with some more IF transformers. Then there is a side board with large transistors on it. This is going to be "fun" to work on. It already has been. I much prefer tube sets.
Thanks for your advice. I will search for those filter capacitors.

Dave...
:Hi again Dave,
:
:Glad you got the Buick radio going.
:
:On these solid state car radios, the piercing tone is usually caused by an open filter capacitor. My 72 Ford/Bendix manual seems to be missing, so all I can offer is from the 71 manual. The filter capacitor is a 3 section can soldered directly to the circuit board. 2-400mfd. sections, and a 1000mfd section. Looking at the printed circuit side of the board, starting at "12-o-clock" on the capacitor, section "C" is 400mfd. 4 o-clock is section "A" 1000mfd. 8 o-clock is section "B" 400mfd. Your 72 may be different.
:
:Sorry I can't help you with the speaker wiring, the 71 manual shows only 3 speaker wires leaving the radio. Orange is left audio, white is right audio, and violet is ground (speaker common). Audio comes directly from the output auto-formers, no output capacitors.
:
:Meade
:
:
:
:
::Hello All,
:: This set is from 1972. I hope it's not too new for this forum. I am getting a very loud ear piercing tone from the speakers on AM. If I touch one of the speaker wires, it gets louder. If anyone has any ideas what could cause this problem, please help. Also, the volume is not as loud as it should be. Both AM and FM work.
::
::Thanks,
::
::Dave...
::
::Which wire is which for the speakers?:
::
::Orange with stripe?
::Pink with blue tracer?
::Pink with grey tracer?
::Ivory?
::Black with white stripe: Speaker common.
::
::
::No matter how I hook up the wires, the fader fades from left to right instead of front to rear. Maybe the output capacitors are defective.

Meade,
There is no can in this set. The electrolytic capacitors are all over the place. The set seems to be impossible to open up so that I can get to the screws so that I can unsolder the capacitors and install new ones. This is a puzzle. It's different from the one with 125 at the end of the model number. I have a copy of that SAMS photofact and it's nothing like the set I have in front of me. This set has at least 3 PC boards in it.

Thanks,

Dave...
:Meade,
: I thought it was something like that. This set's PC boards are so jammed in, it's hard to find anything. The FM and front end board is screwed to the back. There is a top board with AM circutry and tuning mechanism, and a bottom board with some more IF transformers. Then there is a side board with large transistors on it. This is going to be "fun" to work on. It already has been. I much prefer tube sets.
: Thanks for your advice. I will search for those filter capacitors.
:
:Dave...
::Hi again Dave,
::
::Glad you got the Buick radio going.
::
::On these solid state car radios, the piercing tone is usually caused by an open filter capacitor. My 72 Ford/Bendix manual seems to be missing, so all I can offer is from the 71 manual. The filter capacitor is a 3 section can soldered directly to the circuit board. 2-400mfd. sections, and a 1000mfd section. Looking at the printed circuit side of the board, starting at "12-o-clock" on the capacitor, section "C" is 400mfd. 4 o-clock is section "A" 1000mfd. 8 o-clock is section "B" 400mfd. Your 72 may be different.
::
::Sorry I can't help you with the speaker wiring, the 71 manual shows only 3 speaker wires leaving the radio. Orange is left audio, white is right audio, and violet is ground (speaker common). Audio comes directly from the output auto-formers, no output capacitors.
::
::Meade
::
::
::
::
:::Hello All,
::: This set is from 1972. I hope it's not too new for this forum. I am getting a very loud ear piercing tone from the speakers on AM. If I touch one of the speaker wires, it gets louder. If anyone has any ideas what could cause this problem, please help. Also, the volume is not as loud as it should be. Both AM and FM work.
:::
:::Thanks,
:::
:::Dave...
:::
:::Which wire is which for the speakers?:
:::
:::Orange with stripe?
:::Pink with blue tracer?
:::Pink with grey tracer?
:::Ivory?
:::Black with white stripe: Speaker common.
:::
:::
:::No matter how I hook up the wires, the fader fades from left to right instead of front to rear. Maybe the output capacitors are defective.

Meade,
This is a Philco version of the radio. The one in the service data is a Bendix. There is no capacitor can. Taking it apart was easier than it looked. Some wires had to be disconnected. The places where the wires go are marked with a dot of color that matches thew wire. There were only 4 wires to disconnect, and the two halves, separated. There are 15 electrolytic capacitors on the bottom PC board and 1 on the top pc board. As long as I have it open, I'll replace all of them. This should "renew" the radio. I don't think that early 70s electrolytic capacitors were as good as what we have now. So replacing all of them should make a big difference.

Dave...
:Meade,
: There is no can in this set. The electrolytic capacitors are all over the place. The set seems to be impossible to open up so that I can get to the screws so that I can unsolder the capacitors and install new ones. This is a puzzle. It's different from the one with 125 at the end of the model number. I have a copy of that SAMS photofact and it's nothing like the set I have in front of me. This set has at least 3 PC boards in it.
:
:Thanks,
:
:Dave...
::Meade,
:: I thought it was something like that. This set's PC boards are so jammed in, it's hard to find anything. The FM and front end board is screwed to the back. There is a top board with AM circutry and tuning mechanism, and a bottom board with some more IF transformers. Then there is a side board with large transistors on it. This is going to be "fun" to work on. It already has been. I much prefer tube sets.
:: Thanks for your advice. I will search for those filter capacitors.
::
::Dave...
:::Hi again Dave,
:::
:::Glad you got the Buick radio going.
:::
:::On these solid state car radios, the piercing tone is usually caused by an open filter capacitor. My 72 Ford/Bendix manual seems to be missing, so all I can offer is from the 71 manual. The filter capacitor is a 3 section can soldered directly to the circuit board. 2-400mfd. sections, and a 1000mfd section. Looking at the printed circuit side of the board, starting at "12-o-clock" on the capacitor, section "C" is 400mfd. 4 o-clock is section "A" 1000mfd. 8 o-clock is section "B" 400mfd. Your 72 may be different.
:::
:::Sorry I can't help you with the speaker wiring, the 71 manual shows only 3 speaker wires leaving the radio. Orange is left audio, white is right audio, and violet is ground (speaker common). Audio comes directly from the output auto-formers, no output capacitors.
:::
:::Meade
:::
:::
:::
:::
::::Hello All,
:::: This set is from 1972. I hope it's not too new for this forum. I am getting a very loud ear piercing tone from the speakers on AM. If I touch one of the speaker wires, it gets louder. If anyone has any ideas what could cause this problem, please help. Also, the volume is not as loud as it should be. Both AM and FM work.
::::
::::Thanks,
::::
::::Dave...
::::
::::Which wire is which for the speakers?:
::::
::::Orange with stripe?
::::Pink with blue tracer?
::::Pink with grey tracer?
::::Ivory?
::::Black with white stripe: Speaker common.
::::
::::
::::No matter how I hook up the wires, the fader fades from left to right instead of front to rear. Maybe the output capacitors are defective.

I replaced all 16 electrolytic capactitors and the radio works like new. The sound is quite good. Now as to which wire is which. The ivory colored wire is for the left front speaker and the the pink with blue tracer (line running the length of the wire) is the right front speaker. The other two wires are for the rear, and the black wire is speaker and power negative.
Apatently electrolytic capacitors even as late as from the 70s have to be replaced. I thought that capacitors were made pretty well by that time. I was wrong.
Thanks for everyone's help.

Dave...
:Meade,
: This is a Philco version of the radio. The one in the service data is a Bendix. There is no capacitor can. Taking it apart was easier than it looked. Some wires had to be disconnected. The places where the wires go are marked with a dot of color that matches thew wire. There were only 4 wires to disconnect, and the two halves, separated. There are 15 electrolytic capacitors on the bottom PC board and 1 on the top pc board. As long as I have it open, I'll replace all of them. This should "renew" the radio. I don't think that early 70s electrolytic capacitors were as good as what we have now. So replacing all of them should make a big difference.
:
:Dave...
::Meade,
:: There is no can in this set. The electrolytic capacitors are all over the place. The set seems to be impossible to open up so that I can get to the screws so that I can unsolder the capacitors and install new ones. This is a puzzle. It's different from the one with 125 at the end of the model number. I have a copy of that SAMS photofact and it's nothing like the set I have in front of me. This set has at least 3 PC boards in it.
::
::Thanks,
::
::Dave...
:::Meade,
::: I thought it was something like that. This set's PC boards are so jammed in, it's hard to find anything. The FM and front end board is screwed to the back. There is a top board with AM circutry and tuning mechanism, and a bottom board with some more IF transformers. Then there is a side board with large transistors on it. This is going to be "fun" to work on. It already has been. I much prefer tube sets.
::: Thanks for your advice. I will search for those filter capacitors.
:::
:::Dave...
::::Hi again Dave,
::::
::::Glad you got the Buick radio going.
::::
::::On these solid state car radios, the piercing tone is usually caused by an open filter capacitor. My 72 Ford/Bendix manual seems to be missing, so all I can offer is from the 71 manual. The filter capacitor is a 3 section can soldered directly to the circuit board. 2-400mfd. sections, and a 1000mfd section. Looking at the printed circuit side of the board, starting at "12-o-clock" on the capacitor, section "C" is 400mfd. 4 o-clock is section "A" 1000mfd. 8 o-clock is section "B" 400mfd. Your 72 may be different.
::::
::::Sorry I can't help you with the speaker wiring, the 71 manual shows only 3 speaker wires leaving the radio. Orange is left audio, white is right audio, and violet is ground (speaker common). Audio comes directly from the output auto-formers, no output capacitors.
::::
::::Meade
::::
::::
::::
::::
:::::Hello All,
::::: This set is from 1972. I hope it's not too new for this forum. I am getting a very loud ear piercing tone from the speakers on AM. If I touch one of the speaker wires, it gets louder. If anyone has any ideas what could cause this problem, please help. Also, the volume is not as loud as it should be. Both AM and FM work.
:::::
:::::Thanks,
:::::
:::::Dave...
:::::
:::::Which wire is which for the speakers?:
:::::
:::::Orange with stripe?
:::::Pink with blue tracer?
:::::Pink with grey tracer?
:::::Ivory?
:::::Black with white stripe: Speaker common.
:::::
:::::
:::::No matter how I hook up the wires, the fader fades from left to right instead of front to rear. Maybe the output capacitors are defective.