| Products > Test Equipment |
| Hacking the Victor VC-921 |
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| dacson:
I ordered a Victor VC921 recently (24.05.2018), after i only found offers for the Zotek VC921/Aneng 8203 for a while, which is based on a different chipset/design afaik. I was a little bit afraid that the seller didn't know the difference and that i might instead receive a Zotek/Aneng "clone". To my surprise, i really received a Victor VC921, with the tall numbers on the display and the oval buttons. But what's really interesting is that it came with the DM1106EN as QFP instead of as COB, just like in my UT210E. Not sure if this changes anything in regard to hackability as all pins seem to be in use anyway, so i guess a COB would have had all pads bonded as well. Still, i prefer this over a COB with (maybe) unbonded pads under the black gunk. What i don't like is the bend PTC with its bare feet coming quite close to the (i guess) clamping transistors. Solved that with some kapton tape until i have access to my iron again. Edit: Actually, on a second glance, four pins seem to be unused and could potentially be unbonded on a COB. And sorry that this is more of a teardown post, i have a second unit in the mail that i will hack, once i have access to my tools again, and report here. |
| shved:
So, I've needed cheap platform for logging with some degree of safety for some time. After searching, I've found this and similar threads and ordered Victor VC921. Couple days ago the box arrived and I got to work. Chinese seller sent me different rev. The knob and buttons are a different color, PCB rev. is different too. EEPROM editing is simple. Chip is not COB on my rev. it is in TQFP as per datasheet! UART TX pin is small and fiddely to solder a wire to, huge pain in the ass! To insure some safety I've made IR interface as in datasheet example schematics. But added ring - magnet connection like Apple mag-safe. The IR LED and IR photo-transistor can be salvaged from decommissioned electricity meters/counters(same duty there). Also I've added input banana sockets and deleted original probes. Anyway, after I finish the tests, wait for glue and make some stickers - I can take some pictures |
| bffargo:
Thanks everyone for this hack and links and descriptions. I successfully changed my ~7 year old one to 8000 count. I was unable to change any byte past $0080 (like in the Select multi function table). The programmer would write the earlier changes to the count area ($0010) but would get a verify error on the random things I tried above $0080. Anyone else experience this? Any ideas why? On a tangent, I tried to read the 24C02 on my ANENG 8008 and it failed to read at all giving an error during read. Do I need to remove the XTAL or short across it or is it something else? I don't think there are any hacks for it (only the earlier 8002) but wanted to read out the eprom now since I was working with testers. |
| shved:
Photos of my dataloging setup, as promised. |
| shved:
more photos |
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