The HP 10529a thread

Jacklick, was the list of most common ICs and pin compatible ones in this thread or somewhere else? I searched though a couple of the HP 10529a threads but couldn't find it.

KLOV chart of common ICs ->

common_ttl-jpg.183124


 
Sooo ... the DIP clip on my 10529A totally bit the dust. Anyone have any recommended replacements before I attempt to piece one together?
 
I've read about half through this thread so far to get information on how to repair my 10529A. Besides the 74L86 being incompatible with its LS variant, and requiring substitution with an LS386 if bad, are there any other ICs that cannot be replaced with more readily available and less expensive variants (like LS) without causing issues with the comparitor's function?
 
SAM'S ARCADE FIX- Hewlett Packard 10529A Logic Comparator Self-Test Card- Can't find one so let's make one.
Here is my latest video. I have been on a search for a Hewlett Packard 10529A Logic Comparator Self-Test Card so I can find out if my Logic Comparator is working as, it should. I hadn't been able to find one so I had a bright idea, how hard could it be to make one? Well in this video I find out so here it is, and I hope you enjoy the video.
 
I have a weird problem that has caused me many hours of unnecessary troubleshooting. On my clip, the side marked pin1 is actually pin 9. I'm wondering if there is a way to disassemble the clip and flip the plastic sides?

I'm afraid to get rough with it. I know I could re-solder the wires on the opposite end, but that seems silly.
 
label maker :D ... that's odd that its flipped? i don't recall , but if its plugged in on the inside of the case, maybe the plug is flipped around?
 
This was discussed 10 years ago in this thread but might need an update as exact parts are getting harder to find.

My U5 IC is bad. Orig part is HP 1820-0598. Seems like the replacement back in the day was a 74L86. Those were hard to find so 74LS386 was a good substitute. (The 74LS86 is NOT an equivalent). 74LS386s are hard to find now too but are at a few places.

But I want to order from Digi-Key because of other stuff. Is SN74AC86N a usable alternative in this case? They have those in stock.

I believe it's pin compatible and being an "AC" just means it's faster and uses less power, right?

Just want confirmation before I place the order and document here to maybe help someone in the future.
 
I went thru this repair a couple of decades ago; the L86 has a different pinout than other xx86 parts. The LS386 was chosen because it matches the L86 pinout. Check the datasheets to be sure. Jameco has them in stock.
 
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I have stock of L86...
Thanks but my post didn't get much traction so I just bought the stuff I needed and paid the shipping costs. I have a few on the way, and some LS386s to have on had as well.

I tried an HD7486P from a spare board I had, but that didn't work. Couldn't find a datasheet on it so I just bent the pins wide (didn't solder it in). It did activate the "dead" LEDs but then other ones wouldn't work so I'm guessing its pin out is not exactly right.

The stuff arrives tomorrow so I should know soon if it's fixed.
 
Hi all - I've recently obtained a HP-10529a comparator and when running the test card - LED 16 is stuck on permanently - the other LED's flash ok. Poking around I found the diode at CR8 had gone so I replaced this. However looking at the inputs of U6C - pin 9 pulses ok but pin 8 is stuck high - this is fed from U4C pins 6 (high) and 5 (low) constant - I've swapped c14 with c16, r14 with r16 and c13 with c15, also swapped cr7 and cr8 just incase it was a bad replacement diode - but the fault doesn't move from led 16

Any ideas on what to check next ?

Nik


Screenshot 2025-05-26 at 18.41.59.png
 
Thanks but my post didn't get much traction so I just bought the stuff I needed and paid the shipping costs. I have a few on the way, and some LS386s to have on had as well.

I tried an HD7486P from a spare board I had, but that didn't work. Couldn't find a datasheet on it so I just bent the pins wide (didn't solder it in). It did activate the "dead" LEDs but then other ones wouldn't work so I'm guessing its pin out is not exactly right.

The stuff arrives tomorrow so I should know soon if it's fixed.
The 74LS386N fixed the issue.
 
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You needed a 74L86 and not an LS or blank... the pinouts are different.
 
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