ACP Components entire inventory for sale

[uncle_bob]

Hi

If you can send me a picture of the proper markings .... Bob's Custom IC's can get you some chips

Once things get scarce and expensive, the re-marking guys come in. We yell a lot about eBay and this sort of thing. It occurs through much more formal channels than that and more often than it should. After the parts travel through a number of hands, knowing what is real and what is "not quite" can get pretty tough.

Bob

Hi Bob,
I'm not really sure what the proper markings might be, although I've seen plenty of the fake Z80 CPUs on eBay

Actually I've just popped back to this thread to mention that I had another look on eBay while I was thinking about it, and unexpectedly found someone selling thirty Z8410APS DMA chips for $8.25+P&P, so I've just bought them all.

http://www.ebay.co.uk/itm/272147447127
the listing makes a big deal about counterfeiting, so I imagine he's a legit seller?

I guess now I need a dusty box of Z80 PIO's


edit:
oh again, someone selling ten Z0842004 PIO for £7.50 and ten Z0843004 CTC for £4.99, so that's handy.

OK, so now I need a dusty box of 32Kx8 RAM

Hi

You may get legit chips. In that case, you use them and they are gone. You may get "other chips". In that case they go in a box and sit until you have time to figure out what's going on. The eventual result is that there are fewer good chips and more "other chips". If somebody comes along and buys your whole stash of chips, they all look fine. They don't have your knowledge of where the chips came from and what happened when the first one was plugged in.

Crazy!

Bob

[iampoor]

Indeed. I've got a stash of a couple of hundred OC and 2N germanium transistors I'm going to dump on eBay when the prices get silly again. As in £15 a transistor silly

I actually remember in the early 1980s my mother worked in a radio repair shop and they were retro fitting silicon transistors to some radios because the germanium ones were snuffing it. They were crap then as they are now!

If you ever find any lots that you wouldn't mind letting go at less silly prices, shoot me a PM.  characterizing them is quite frustrating, but they DO sell. Just gotta find some low leakage ones (I do build guitar pedals, if it isnt obvious by now haha!)

I elieve it. I cant imagine how low the lifespan of germanium transistors must have been in hot environments with lots of vibration.

Chara

[MrSlack]

Indeed. I've got a stash of a couple of hundred OC and 2N germanium transistors I'm going to dump on eBay when the prices get silly again. As in £15 a transistor silly

I actually remember in the early 1980s my mother worked in a radio repair shop and they were retro fitting silicon transistors to some radios because the germanium ones were snuffing it. They were crap then as they are now!

If you ever find any lots that you wouldn't mind letting go at less silly prices, shoot me a PM.  characterizing them is quite frustrating, but they DO sell. Just gotta find some low leakage ones (I do build guitar pedals, if it isnt obvious by now haha!)

I elieve it. I cant imagine how low the lifespan of germanium transistors must have been in hot environments with lots of vibration.

Chara

I'll list some on ebay shortly and post here. I've designed a semi-automatic rig for characterising them as I've got so many. I haven't tested it yet. Basically it's a hard reference voltage (lm317) set at 9.000v and a few resistors which are selected from a batch of 5% ones that set the collector current and base current accurately. The base is open circuit by default but a computer controlled relay closes to connect the base current. My UT-61E is connected to the PC and a python script controls the relay and reads the voltages form the meter. All you do is plug a transistor in, press enter, it waits for the quiescent state to settle, measures the leakage then the relay closes and it measures the gain. The gain is adjusted against the leakage current as well. Out pops two values, write them on the bag, stick on ebay. Goto 1.

Whole rig is battery powered to avoid ripple, transients etc.