#1306 Heathkit Frequency Counter IB-1102 (part 3 of 4)

Показать описание

Episode 1306
wrong board? wrong schematic? wrong part?

Рекомендации по теме

Комментарии

Thankfully the donator had all the extra parts/ICs to give you. Nice repair !!

romancharak

PLEASE scan that 1102 book and upload it. Preservation is so important. 👍

pcwrangler

Excellent - glad I didn't run into "engineering changes" like those on my 1103!

jrkorman

The sockets are Molex Soldercons. Age appropriate for the time. You bought them on a long strip, cut off the number of pins you needed, soldered them in, then broke off the tie strip.

sleibson

In my experience, *about* half of all failures in electronics circuits are visible under close inspection. For new items that never worked, the build error is often visible. For older (previously working) items, the failures are still very often visible (but beware of root cause of course). Close inspection and common sense doesn't need a schematic, as it's not troubleshooting (simply visual inspection). I always go straight to close visual inspection before even starting logical troubleshooting.

For the mysterious solder bridge, if there's not a trace under it, then it's probably a mistake (especially considering: Heathkit). One could look up the IC datasheet, and see what the pins are.

JxH

Yes, these are front-end ECL parts used before frequency division. You want speed, you get heat!

utoothheartyeight

We had a Heath frequency counter at trade school similar to this. It had multiple push buttons to select different ranges other than Khz/Mhz. It had a 567 PLL that would multiply low frequencies (below 100 Khz?) so you couls get .1 or .01 Hz resolution for audio frequency measurements. I sat with my instructor while he worked on it. Yep, the main filters were bad - this was back in 1980. That TCXO is temp compensated, not an oven. I wonder if that board went in another counter like the one we had at school.

rfburns

About the difference between the board and the schemmatic: I had the same problem with my Boonton 92C. The power supply stage in the schemmatic, it was different from the board. I spent a lot of time searching for the correct schemmatic.

xandear

Yes, please scan and upload the manual. The vintage radio site is missing that one. I just picked up an 1102 and could really use it. :)

button-puncher

Great work, so what is left for (part 4 of 4)?
Checking the timebase? its temperature behavior after switching on, - or the frequency and amplitude limits?

Manf-ftzk