Hello, I am not sure what to check for the hissing. It sounds like someone is turning a dirty volume knob. After a while, It goes away. All of the caps have been replaced with 10uf caps 450volts. The hissing is soft and can be overcome by turning up the volume. Bad tube? If thats the case I'll have to get spares to try. I did clean the volume control with radio shacks tv tuner cleaner. What is a good thing to use to clean tube sockets?

Hello, I have used auto zones carburator cleaner to clean spilled stuff from circuit boards..works pretty good, will this stuff clean contacts ok? Its real cheap too$1.29 will get you a big can of it.

:Hello, I am not sure what to check for the hissing. It sounds like someone is turning a dirty volume knob. After a while, It goes away. All of the caps have been replaced with 10uf caps 450volts. The hissing is soft and can be overcome by turning up the volume. Bad tube? If thats the case I'll have to get spares to try. I did clean the volume control with radio shacks tv tuner cleaner. What is a good thing to use to clean tube sockets?

Hi,
Carb cleaner is not a good thing to try on a radio,as there are many radios with a softer plastic used in the switches, and carb cleaner just melts them to nothing.

Auto Zone should carry LPS products, and LPS 1 is superior to carb cleaner in radio applications, and one of the best things I have found so far for cleaning contacts, freeing up stiff controls, and cleaning switches. The carb cleaners are formulated a bit different from one brand to the next, but all are designed to disolve varnish, and they do not leave any residue at all- which can be a problem for some items- Pots especially, because without a little bit of lubricant, you can rub the carbon off in no time at all.

As far as the hiss is concerned, you may have a a bit of leakage in the cap in the audio stage, but once ina while it may be from an external noise source too. It could also be a cold solder joint, or a loose component within a tube, or even corrosion on a tube pin.

Best thing for clenaing tube sockets is a product called "Rail Zip". It is used for cleaning model railroad tracks. A slight amount on each pin is often enough to apply, and the tube can be rocked a little bit to ensure good contact.

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:Hello, I have used auto zones carburator cleaner to clean spilled stuff from circuit boards..works pretty good, will this stuff clean contacts ok? Its real cheap too$1.29 will get you a big can of it.
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::Hello, I am not sure what to check for the hissing. It sounds like someone is turning a dirty volume knob. After a while, It goes away. All of the caps have been replaced with 10uf caps 450volts. The hissing is soft and can be overcome by turning up the volume. Bad tube? If thats the case I'll have to get spares to try. I did clean the volume control with radio shacks tv tuner cleaner. What is a good thing to use to clean tube sockets?