im repairing my 1968 roundie color, chassie # T938 its had a color problem since i picked up ,havent really got into till now . from the looks of it im wondering if this was hit by lighting, from cap c101 on line input .047 was exploded and other signs ,the question i have theres a diode CR101 prt #530097-3 / gecr-2 /or ecg119 it seems to be open ,now my nte book doesnt even show a discription of this # whats the modern replacement for it and some info on it, all i know is its a high voltage rec. type ,and its not a zener diode. its in line for the 1200 v boost ,was this diode a problem and was it updated. thanks for your help

My old ECG book shows it as a Selenium diode, 590 PIV, 2.2 mA peak current.

I would think that a 1N4007 would work fine...

My old ECG book shows it as a Selenium diode, 590 PIV, 2.2 mA peak current.

I would think that a 1N4007 would work fine...

thank you sir, what yr was your ecg book

80-something. Covers are long gone...

I have a GE CR-2, NOS, if interested. Send me a PM if you want it.

I have a GE CR-2, NOS, if interested. Send me a PM if you want it.

thanks for the offer , i have 1n4007 and color looks better now to. were these a problem in the day i found another ge-2 in a retired tv guys tool box ,but it was open to.

It is a boost diode, it is a fast recovery, high voltage, low current device operating at scan frequency. It should be replaced with the same type. Failure causes low CRT screen voltage and therefore poor brightness.

A typical 1N4007 series diode will get hot and soon fail. Boost diodes should be plentiful.

It is a boost diode, it is a fast recovery, high voltage, low current device operating at scan frequency. It should be replaced with the same type. Failure causes low CRT screen voltage and therefore poor brightness.

A typical 1N4007 series diode will get hot and soon fail. Boost diodes should be plentiful.
yes i think you might have something there ,after running awhile with the 1n4007 installed i have noticed my color is having a stablizing problem but cold its better ,do sujest any number besides 1n4007.

hey i found nos nte506 that should work good as a replacement.

The original was a selenium. Since when do Se rectifiers exhibit faster recovery time than modern Si types?

Sure, a fast recovery diode would be "better" for rectifying 15 kHz pulses, but such things didn't exist when the set was built, AFAIK.

When I found a bad boost diode in my Silvertone roundy a few years back I replaced it with a high voltage diode from radio shack. I can't remember the number, but it did have a speck of 1000V or more listed on the face of the package IIRC. It has lasted over 2 years in regular use without issue.

it looks like the nte506 works pretty good ,it has 1400 prv / trr-500ns / vf-v1.0@1a /If-2a/Ifrm-3.5a/ si fast recovery diode

i need help i.d. a v.d.r in the vert section of this magi ch#t938 vdr501 part number 230167-5 it tested open no resistance and sams doesnt give a value for it ,i like to find what is a modern replacement for it .thanks if someone can help