Those blue plastic solid state late 70s scopes Heathkit (and made for Bell &
Howell schools) put out were the worst...Id part it out and cut your losses.
The only thing good about them were the flatface CRTs.
If you can find the manual for the 4555 look for the single trace model its
the same power supply.
Speaking of
I just had a fun day rebuilding a power supply and matching 6AW8 vertical PP
amplifier tubes for a DC coupled Paco S-55.....Good looking --but piece of
crap like my ex.

One of the worst pieces of junk made
wrote in message
...
Hi, I have an IO-4555 Heathkit O-Scope that started spewing out smoke
15 seconds after turning it on.

Would like to find someone that can shoot me a PDF of the assembly
manual with schematics. The operations manual would be nice also.

I've checked Google and Dogpile for variations and can only find a
schematic for the dual trace version. (IO-4550)

A few places are selling the manuals for a goofy amount of money. I
may have some files, templates, webspace, etc. that I can offer for
trade.

Tim - WD8MQF


http://www.frakkedmatch.com

.. .
Hi, I have an IO-4555 Heathkit O-Scope that started spewing out smoke
15 seconds after turning it on.

Pull the cover, apply power. Look at where the smoke is coming out. If
it's coming out of the power transformer, which it almost certainly is,
pull the tubes and discard it. Nothing else is really worth saving, not
even the switches and connectors.

If it's just a power supply cap failing, you may be in luck. But what
mostly fails on those things are the high voltage secondary winding on the
power transformer, which were very close to breaking down even when they
were new. There are very narrow safety margins on those things. Everything
in these scopes was designed to be cheap.

Would like to find someone that can shoot me a PDF of the assembly
manual with schematics. The operations manual would be nice also.

I've checked Google and Dogpile for variations and can only find a
schematic for the dual trace version. (IO-4550)

That should be sufficient since what is failing is almost certainly in the
power supply anyway, which should be identical.

A few places are selling the manuals for a goofy amount of money. I
may have some files, templates, webspace, etc. that I can offer for
trade.

Heath is still around and still selling manuals, and consequently they have
been going after people who make them available for free since they are still
in copyright. I'm okay with that, because they DO make them available at
what would be a reasonable price for any piece of equipment that is worth
something. The problem is that those scopes aren't really worth anything....
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Thu, 16 Feb 2012, Scott Dorsey wrote:


Heath is still around and still selling manuals, and consequently they have
been going after people who make them available for free since they are still
in copyright. I'm okay with that, because they DO make them available at
what would be a reasonable price for any piece of equipment that is worth
something. The problem is that those scopes aren't really worth anything....

Wasn't it that Heath had sold off the old manuals to some guy, who having
spent the money, became insistent that he reap the benefits.

There was a long period when those manuals were out there, nobody fussed,
but it was after the new owner got control that things changed.

Michael