D9200 Not Powering On

[zenomorp]

Hey guys. Got another D9200 that won't power on. It clicks a couple times, but doesn't fire up the tube. Any ideas? I have no idea where to start with the common issues (HOT and stuff). All the transistors that resemble the HOT aren't shorted. Need some help. Thanks in advance - Mike.

 

[nuterpacman]

Check 2n7000 fet transistor and resistors,etc... around uc3842 ic up and left of flyback area.

 

[zenomorp]

Check 2n7000 fet transistor and resistors,etc... around uc3842 ic up and left of flyback area.

Thanks. I'll check 'em out.

 

[zenomorp]

Check 2n7000 fet transistor and resistors,etc... around uc3842 ic up and left of flyback area.

Hmm. Can't seem to find them.

 

[modessitt]

I got one that did that (couple clicks then nothing). turns out the yoke was fried.

Now, if it clicks a lot, check the HOT...

 

[modessitt]

BTW - the D9200 has some memory corrupt problems, too, so if you're trying it in VGA with no image, try hooking it up to CGA (or vice versa) and then getting into the OSD menu and do a Memory Recall.

I recently ran into one that needed just that to fix it...

 

[zenomorp]

I got one that did that (couple clicks then nothing). turns out the yoke was fried.

Now, if it clicks a lot, check the HOT...

Well, I am testing it on a known good tube and yoke. The picture is great with a U2000 or a K7000. The D9200 just clicks a few times and does nothing. Also, I don't know which transistor is the HOT. There are 4 possibilities.

 

[modessitt]

Well, I am testing it on a known good tube and yoke. The picture is great with a U2000 or a K7000. The D9200 just clicks a few times and does nothing. Also, I don't know which transistor is the HOT. There are 4 possibilities.

Um - What "known good tube and yoke" are you testing it on? Are you using the same tube that you used to test the U2000 or K7000?

If so, then that's your problem. The yoke for those isn't the same as for the D9200. And since the D9200 had a bonded yoke (meaning you can't pull it off without shattering the tube), you can't swap one on to a different tube for testing purposes...

 

[zenomorp]

Um - What "known good tube and yoke" are you testing it on? Are you using the same tube that you used to test the U2000 or K7000?

If so, then that's your problem. The yoke for those isn't the same as for the D9200. And since the D9200 had a bonded yoke (meaning you can't pull it off without shattering the tube), you can't swap one on to a different tube for testing purposes...

I'll try a correct tube then. . Thanks for the info. Didn't know that.

 

[modessitt]

I have recently discovered that there are versions of the D9200 tubes that have removable yokes (WG sells a replacement if you don't have a bonded yoke)....