[SOLVED] What is this component?

[mozart1973]

Hi!

Found this components. What are they?

Is one of them in bad shape?

They sit between tuner and antenna.

 

[tpetar]

Its capacitor.

But one is wounded.

 

[albert22]

High voltage capacitors probably ceramic.
1 nF is the value for the capacitance ( 1 nano Farads)
5 Kv the voltage that their are capable of withstand (5000volts).
Are you talking about a Ham radio antenna tunner ?

 

[mozart1973]

High voltage capacitors probably ceramic.
1 nF is the value for the capacitance ( 1 nano Farads)
5 Kv the voltage that their are capable of withstand (5000volts).
Are you talking about a Ham radio antenna tunner ?

No, just an old am/fm tube radio. The fm band doesn't recieve anything. These capacitors are solded between the fm antenna socket and some coil next to the tuner.
Why it needs to be 5000 volts is odd to me. and why does it say TEST.

 

[albert22]

Such high ratings are usual for transmitting antenna tuners. In this case it may be over rated just for security. Take care with old tube radios because they used to have a "hot" chassis. That is the chassis is connected directly to mains.
The capacitor blocks harmful voltages so you dont get a shock if you touch the FM antenna. I guess that 1000v is ok.
I dont think that the problem is caused by the capacitors. If the two capacitors are in parallel the radio will receive normally with just one of them.
If you hear no noise at the fm band then certainly the problem is somewhere else. You can test by connecting a length of insulated wire as a temporary antenna bypassing the capacitors. take care though the wire could be "hot" is not the final solution.

 

[mozart1973]

Such high ratings are usual for transmitting antenna tuners. In this case it may be over rated just for security. Take care with old tube radios because they used to have a "hot" chassis. That is the chassis is connected directly to mains.
The capacitor blocks harmful voltages so you dont get a shock if you touch the FM antenna. I guess that 1000v is ok.
I dont think that the problem is caused by the capacitors. If the two capacitors are in parallel the radio will receive normally with just one of them.
If you hear no noise at the fm band then certainly the problem is somewhere else. You can test by connecting a length of insulated wire as a temporary antenna bypassing the capacitors. take care though the wire could be "hot" is not the final solution.

Ok, have touched the chassis. Nothing happens. But good tip for future projects.

Good thing that only 1000v is sufficient. 5000v is not easy to find.

I found the sinner. In the tuner sits a tube. If wigling it to a certain position fm works. I bit odd cause the pins do not look corroded at all. I may have to clean it thoroughly and that mean taking the chassis out and that is not easy on this radio. But I may have to anyway if I have to change all the capacitors due to hopefully get rid of the buzzing.

Anyway, thanks for your input.

 

[albert22]

Two 2nF x 1000v in series makes 1nF x 2000v.
That is: for N capacitors in series connection you divide the cap value by N and multiply the voltage by N.