K4900 diode question

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Hi;
I am rebuilding a 4900 and found 2 broken (physically) diodes located at D304 and D305. I checked the manual and they are listed as RH-1V (RH-IV?). I tried Google, NG. I tried searching the forums and again struck out.
Does anybody know what these diodes are? Or a possible cross?

Any help will be very much appreciated.
Thanks
Jeff
 
Hey man - thank you very much for taking the time to do that for me - much appreciated!
I had forgotten to try that, next time I will.....

So it looks like it is a Fast Recovery, 1A 600V rectifier. Should I just go with the NTE or would any FR diode in that V/A rating do?

Thanks again for your help
Jeff
 
No problem. I am in the process of cap kitting and troubleshooting a K4900 myself. But out of the 4 listed that came up at mouser.com, I am not sure which would be the proper diode. I would like to say go with the $1.55 diode because the others are quite expensive.

Hopefully, one of the monitor gurus on KLOV could verify.
 
No problem. I am in the process of cap kitting and troubleshooting a K4900 myself. But out of the 4 listed that came up at mouser.com, I am not sure which would be the proper diode. I would like to say go with the $1.55 diode because the others are quite expensive.

Hopefully, one of the monitor gurus on KLOV could verify.

1N4937 is a fast recovery diode rated at 1A 600V and is as cheap as chips (pennies)
 
Now that's what I'm talking about!
I hate NTE as they tend to bang you out when they can but sometimes you have no choice.....
I might even have the 1N4937 in stock, I'll have to check.
Thank you for the cross-ref.
Jeff
 
1N4937 is a fast recovery diode rated at 1A 600V and is as cheap as chips (pennies)

I checked and I have the 1N4947 in stock, it is rated at 1A 800V and is a fast recovery. I'll just go ahead and use it....

Thanks for the $$$$ savings, much appreciated.....
 
Id check your big white resistors too if you have bad diodes. Was the fuse blown? Last 4900 i worked on had two bad diodes and the white resistor where you measure b+ was open
 
I kinda put this on the back burner because of other stuff but I will check them......
Thanks for the tip.
Jeff
 
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