HP 32E repair

[Harald]

Since Etienne now has my 32E (I hope he is enjoying it as much as I am enjyoing the 34C I got from him!) and I came accros a cheap non working one, I bought it :-)

I wonder what the problem is. When it sat for a while it very briefly turns on. Just enough to see 0.0000 light up for a few milliseconds. Then it goes dark. Initially I thought this would be a power supply issue. But the 6.5V and 5V display voltages are present. Has anybody experienced this problem as well? Any thoughts on what this might be? There is no excessive current drawn, just about 60mA, which appears about right for a spice with no LEDs lit.

Any thoughts appreciated,
Harald

[Harald]

I got it working. It seems to have been a bad ROM chip that caused the problem.

[ElectroDuende]

(11-12-2015 07:25 PM)Harald Wrote:  I got it working. It seems to have been a bad ROM chip that caused the problem.

Lucky you!

I'm still looking for a display for mine... but every spice I find on e-bay (even non working untis) are far more expensive than what I paid for the first unit...

[rprosperi]

(11-12-2015 07:25 PM)Harald Wrote:  I got it working. It seems to have been a bad ROM chip that caused the problem.

Hmmm.... 12 hours to diagnose and replace a bad ROM chip. You may be slipping Harald...

[Harald]

(11-17-2015 02:19 AM)rprosperi Wrote:  Hmmm.... 12 hours to diagnose and replace a bad ROM chip. You may be slipping Harald...

;-) That was the time needed to dig through my partsbox and find a good rom chip :-)

[rprosperi]

(11-17-2015 08:17 AM)Harald Wrote:  

(11-17-2015 02:19 AM)rprosperi Wrote:  Hmmm.... 12 hours to diagnose and replace a bad ROM chip. You may be slipping Harald...

;-) That was the time needed to dig through my partsbox and find a good rom chip :-)

While the parts box of a friend in the same hobby is always something one would like to look thru, in this case it sounds really interesting if it included a good ROM for an HP-32E. Now that's a complete set of spare parts!