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KC9UDX
February 5th, 2014, 03:27 PM
I have three 6581s that all have issues.

One only emits buzzing noise, one has only one working sound channel, and one is just plain quiet. I have verified in each case the problem is in the chip. I am surprised to find this because I don't remember the SID chip being problematic.

I used to have two that I bought new ~1988 and for some reason they aren't where I left them!

Does anyone know where to get good working ones? (Without breaking the bank?)

giobbi
February 6th, 2014, 01:29 AM
I have three 6581s that all have issues.

One only emits buzzing noise, one has only one working sound channel, and one is just plain quiet. I have verified in each case the problem is in the chip. I am surprised to find this because I don't remember the SID chip being problematic.

I used to have two that I bought new ~1988 and for some reason they aren't where I left them!

Does anyone know where to get good working ones? (Without breaking the bank?)

did you look on eBay? They tend to appear for sale on a regular basis...

KC9UDX
February 6th, 2014, 08:17 AM
Yes. Some of them looked extremely suspicious, and some were outrageously priced. I put in an offer on one, we'll see what happens.

Is eBay the only source these days?

KC9UDX
February 6th, 2014, 12:18 PM
I ordered some, hopefully they work.

vwestlife
February 6th, 2014, 12:33 PM
Watch out for fake/remarked SID chips from China, though. Usually they are defective chips with new markings painted on them. Companies have been cannibalizing C64s for SID chips to put in products like the SidStation, and the bad ones that were supposed to get thrown out ended up going to unscrupulous resellers instead.

More info here: http://kevtris.org/Projects/sid/remarked_sids.html

rittwage
February 6th, 2014, 03:44 PM
They are an odd hybrid analog/digital chip. Unfortunately, Commodore didn't design them to last 30 years, so it's hard to find 100% good ones anymore. :)

vwestlife
February 6th, 2014, 06:53 PM
Maybe if you dig through the environmentally hazardous waste at the former MOS plant in PA, you can find some SID chips buried there. :)

giobbi
February 7th, 2014, 09:16 AM
Watch out for fake/remarked SID chips from China, though. Usually they are defective chips with new markings painted on them. Companies have been cannibalizing C64s for SID chips to put in products like the SidStation, and the bad ones that were supposed to get thrown out ended up going to unscrupulous resellers instead.

More info here: http://kevtris.org/Projects/sid/remarked_sids.html

At least, you can always use the Paypal buyers protection program; I think in case the SID doesn't work, you can argue you simply didn't receive the parcel and ask your money back.
I did it in the past, when I didn't receive the parcel, and Paypal refund me without problem at all.

KC9UDX
February 17th, 2014, 01:34 PM
My SIDs arrived Saturday. I installed all three in one C64C, (one at a time,) to compare them, and they all perform identically. Actually, they compare much better than I expected. I have nothing else to compare them to, but at least they all work exactly the same, and they seem to work just fine. I think two were from '82 and one was from '84, replacing one from '82, one from '83, and one from '89. I installed them in three machines, one C64 and two C64C's, and they perform as well as I'd expect.

http://www.ebay.com/itm/Commodore-64-128-SID-MIDI-synth-chip-6581-Tested-Good/301072286061?_trksid=p3693.m2452&_trkparms=aid%3D333005%26algo%3DRIC.FIT%26ao%3D1%2 6asc%3D265%26meid%3D4908760920677268246%26pid%3D10 0102%26prg%3D1140%26rk%3D1%26rkt%3D1%26sd%3D301072 286061%26

Now, I notice pretty frequent video "sparkle" on the C64. I don't recall it doing that in the past, but it may have. It's been sitting idle on a shelf for about two years. I wonder if there's some kind noise at the VIC-II. Unfortunately, I didn't notice this whilst it was on the bench. I probably won't disassemble it to investigate it though unless it gets worse.

barythrin
February 17th, 2014, 01:47 PM
Does $29 rival the price of a full C64 still?

KC9UDX
February 17th, 2014, 02:49 PM
I have no idea. What is the market rate for a C64? I didn't pay that much, anyway.

If you do pay that much for a C64, do you know if it has a working SID?