RE: LV2000 demands

> What's in the Zanen kit? I've never used one of those either...

just all the caps and the components for the LV section.. and for some
reason they included the HV adjust pot.. I'll usually install everything
except the pot and the MPSA56. I always go ahead and install all the power
transistors and I keep the ones from the monitor that still test good..

> Does it upgrade the MPS-A56 to an NTE50-like package, like
> is in Gregg's FAQ?

no but that is the KEY to a working WG.. I do that to all my monitors. I
know I still have a couple monitors that have the TO-92 parts in them and
are running strong but I need to swap them out soon, you NEED the heavier
part in there...

> What does
the kit replace the Zeners with?

I dont remember.. I think they are 28V parts.. I've had my own stock of
them so I used them.

> When I've rebuilt LV sections, I've replaced the Zeners with
> 1N4750s (1W, 27V Zener) and Q101 with an NTE/ECG50. I replace
> the smoked resistors with whatever wattage they originally were, and
> leave the other diodes as 1N914s as well...

I recall the original parts are 28V 1W zener and I used the 27V 1W ones
because they were easier to find.. or maybe it was vice versa? I know the
ones I used were a volt off..

There is a surplus place in Minneapolis called ABC electonics that had the
large case (I think it is the TO-202 style) MPSA56s for like $.10 each a
couple years back so I just bought a ton of them..

> Q100 failures are rare in my experience, so I just leave them
> as MPS-A06

yeah I've seen maybe 2 failures of that one..

> It's also my opinion that you're better off without a Zanen
> kit when fixing these monitors. I've never had a cap-related problem
> on the deflection board. On the HV board -- yeah, but never on the
> def. board. When I found out the Zanen Amplifone kit had sub-speced
> parts, and the G08 kit had sub-speced parts, I decided to shy away
> from them for vector monitor repair. Their Raster monitor kits are
> still great, however!

Yeah, but the kit is a good start because it is cheap.. Like I was saying
earlier I buy them for the power transistors, and the caps DO need to be
replaced in the HV cage.. I've had a few problems related to them in the
past such as jitters.. I've never gone near thier GO8 kit.. Then again I
dont really like going near GO8s and I still have like 4 broken ones to
get going.. one of these days I'll dig in.

This brings up another question I was wondering about.. What do you all
think about the HV voltage level.. I recall a conversation I had a while
back with somebody who was saying that running the HV lower will be easier
on the monitor.. I say it doesn't really matter as long as its not over
20Kv and under 16KV, but there is certainly a reason why it is supposed to
be set at 19.5Kv.

I got an HV probe a couple months back and for shits and giggles I checked
a lot of my monitors and found that most of them were running at about
15-17KV. I bumped them all up to 19KV but there is no noticable difference
anyway, the picture stayed the same size between 16 and 19Kv. whaddya
think?

 Jeff
Received on Fri Nov 13 18:32:28 1998