[time-nuts] HP5370B & HP5345B Front-End IC Redesign Effort

Don Latham djl at montana.com
Wed Jan 27 19:38:45 UTC 2016

Someone has already probably said, watch out for switching regulators.  BTW,
almost all the Hp instruments I have from the 80's era run hot as heck. I have
put on fans and piggybacked more fins (and more fins, and more fins...).  A
Military version of the 5328A counter I have has what sounds like a leaf
blower in it, with a proportional controller added.
If you do some work with switchers, I'm sure the list would be very interested!

Perry Sandeen via time-nuts
> Hi,
> Wrote: Since the front end chips are mixed signal ASIC’s, it will take more
> than a bit of time to replace them directly. Re-doing the entire front panel
> board is the most likely way to “fix”the problem. The question is - why do
> that at all? Just do a PC instrument that does the same thing as the counter
> with way less effort…..
> Well, I have two reasons not to.
> First I have about $1800 invested in my 3 5370’s including  the new CPU boards
> and blowing that off is not in my budget. I’ll kludge the living daylights out
> of my units before blowing off my investment.
> Second, I haven’t the slightest clue on how to do a PC instrument and I have
> to many other projects to finish to learn something new.
> Also there was much discussion about A and B cooling in the past and it seems
> the only things some did to their units was the addition of fan(s) on the
> cooling fins.  I had an external fan on a B I was running and the thing still
> was too hot.
> IMNSHO, I believe the front end chip failure is aggravated by the high
> interior heat level.  I’m committed to a number of other projects so it will
> be a while before I can work on mine.
> I’ll either rip the whole PS out and put it on another chassis, try better 3
> terminal regulators instead of the installed pass transistors, install
> switching regulator PS’s in place of the original PS, cut holes in the top lid
> and install 10 or 12 computer fans. Or a combination of the afore mentioned.
> I don’t give a rat’s behind how it will look. I’m only interested in it
> working properly.  I’ve spent 50 years in the electronics industry and I will
> find a way to skin this cat. I’ve done this to other equipment before. And
> when done I’ll tell the list how I did it.
> Regards,
> Perrier
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.

Felix qui potuit rerum cognoscere causas.
Lucky is he who has been able to understand the causes of things.
"Noli sinere nothos te opprimere"

Dr. Don Latham, AJ7LL
Six Mile Systems LLC, 17850 Six Mile Road
Huson, MT, 59846
mailing address:  POBox 404
Frenchtown MT 59834-0404

VOX 406-626-4304
CEL 406-241-5093
Skype: buffler2

More information about the Time-nuts_lists.febo.com mailing list