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5R312 zenith
7/13/2006 1:33:55 PMpaul etheridge
the 6x5 tube gets very bright red when i turn on set., im not sure why, i think the radio has been worked on before., it only shows 2 electrolytics, both seem ok, HELPPPP
7/13/2006 4:27:09 PMNorm Leal
Hi Paul

Either electrolytic cap or tube is usually shorted. Don't operate a radio with a short. The power transformer will de damaged.

Be sure electrolytic caps are rated 450 volts or at least more than voltage in your radio.

Norm

:the 6x5 tube gets very bright red when i turn on set., im not sure why, i think the radio has been worked on before., it only shows 2 electrolytics, both seem ok, HELPPPP

7/14/2006 5:45:16 AMpaul etheridge
:Hi Paul
:
: Either electrolytic cap or tube is usually shorted. Don't operate a radio with a short. The power transformer will de damaged.
:
: Be sure electrolytic caps are rated 450 volts or at least more than voltage in your radio.
:
:i put new caps and 6x5 in, but it still does it, does this radio have chassis ground for the caps and does the wirewound res. look like a normal resistor, i dont see any res. that looks different
:
:
:
::the 6x5 tube gets very bright red when i turn on set., im not sure why, i think the radio has been worked on before., it only shows 2 electrolytics, both seem ok, HELPPPP
7/14/2006 6:34:23 AMNorm Leal
Hi Paul

Notice R8 & R9 are wire wound resistors. They should look different than others in your radio.

http://www.nostalgiaair.org/PagesByModel/984/M0024984.pdf

If you have to operate your radio use a 60-100 watt lamp wired in series with the AC line until the problem is found. The lamp will light if there is a short.

Something is drawing too much current off pin #8 of your 6X5. Usually it would be a problem with C12, C13 and/or the 6X5. Be sure the two caps have a high enough voltage rating and not reversed. In this radio negative goes toward the speaker field. These caps no not used chassis as a connection but chassis is ground for your radio.

Also replace cap C8, .05 mf. It's between B+ and chassis. Other than that look for any wires shorting.

Norm


::Hi Paul
::
:: Either electrolytic cap or tube is usually shorted. Don't operate a radio with a short. The power transformer will de damaged.
::
:: Be sure electrolytic caps are rated 450 volts or at least more than voltage in your radio.
::
::i put new caps and 6x5 in, but it still does it, does this radio have chassis ground for the caps and does the wirewound res. look like a normal resistor, i dont see any res. that looks different
::
::
::
:::the 6x5 tube gets very bright red when i turn on set., im not sure why, i think the radio has been worked on before., it only shows 2 electrolytics, both seem ok, HELPPPP

7/14/2006 11:24:08 AMpaul etheridge
:thanks very much, i found it and now it works great, it WAS the .05 cap and the feild coil was loose where the 8mfd was connected, thanks again

: Notice R8 & R9 are wire wound resistors. They should look different than others in your radio.
:
:http://www.nostalgiaair.org/PagesByModel/984/M0024984.pdf
:
: If you have to operate your radio use a 60-100 watt lamp wired in series with the AC line until the problem is found. The lamp will light if there is a short.
:
: Something is drawing too much current off pin #8 of your 6X5. Usually it would be a problem with C12, C13 and/or the 6X5. Be sure the two caps have a high enough voltage rating and not reversed. In this radio negative goes toward the speaker field. These caps no not used chassis as a connection but chassis is ground for your radio.
:
: Also replace cap C8, .05 mf. It's between B+ and chassis. Other than that look for any wires shorting.
:
:Norm
:
:
:
:::Hi Paul
:::
::: Either electrolytic cap or tube is usually shorted. Don't operate a radio with a short. The power transformer will de damaged.
:::
::: Be sure electrolytic caps are rated 450 volts or at least more than voltage in your radio.
:::
:::i put new caps and 6x5 in, but it still does it, does this radio have chassis ground for the caps and does the wirewound res. look like a normal resistor, i dont see any res. that looks different
:::
:::
:::
::::the 6x5 tube gets very bright red when i turn on set., im not sure why, i think the radio has been worked on before., it only shows 2 electrolytics, both seem ok, HELPPPP



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