Search found 177 matches

by TMAOne
Thu Mar 12, 2020 9:24 pm
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Re: Does Anyone Recognize This Pattern?

Sorry for the delayed response. Life tends to get in the way of working on this. And I think it's time to give it up. More on that presently. To answer the specific questions and areas of concern first, yes either the heat sink was fitted for testing, or a clamp-on auxiliary was used and power-ups l...
by TMAOne
Fri Mar 06, 2020 9:18 am
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Re: Does Anyone Recognize This Pattern?

Is this progress? It certainly is different,... Soooo, I got the 2nd vLA82 in the mail, and had no real issues replacing the socket and putting it in. But rather than the crisp black and white stripes I had (if only briefly) before, this is what I get now: 20200306_014724.jpg The image is blurry--th...
by TMAOne
Sun Feb 09, 2020 1:22 pm
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Re: Does Anyone Recognize This Pattern?

Yep, noise is what I had. But also at ULA 32, so the replacement ULA has been killed. Not sure how the computer and I managed to do that, but after some generous support from Charles, I have a second vLA82 on its way through the post. Efforts to revive this computer will have to wait for the mail sy...
by TMAOne
Fri Feb 07, 2020 5:04 pm
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Re: Does Anyone Recognize This Pattern?

Yeah I was afraid of that. Pretty much wraps it up--I've no clock whatsoever on ULA 32 or CPU 6. ...She's dead, Jim.

The ULA had been working, but suddenly quit. Could a failing capacitor in the -5V power circuit do that?
by TMAOne
Fri Feb 07, 2020 9:22 am
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Re: Does Anyone Recognize This Pattern?

Sorry for the triple post. I'm slowly learning to use this o'scope, like when to ignore "noise" zoomed in to look like something its not. Also looking at my ZX81 as an experimental "control" to give me some idea of what I should be seeing when I look at the Spectrum. I think I've clock problems. The...
by TMAOne
Thu Feb 06, 2020 11:03 pm
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Re: Does Anyone Recognize This Pattern?

Okay no pocket oscilloscope. Instead I'm using a CRT one with an "Auto" button for o'scope neophytes. I thought that the output to the monitor and pin 17 of the ULA would be a good set of brackets to start, but already I don't like what I see. Pin 17 of the ULA: Scope 001 ULA 17.jpg Final output: Sc...
by TMAOne
Thu Feb 06, 2020 6:05 pm
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Re: Does Anyone Recognize This Pattern?

I appreciate that Mark. I will definitely consider it once the determination to prove this computer viable is satisfied. Seems like some parts I will have to order, and I usually take the eBay/China/slow boat route, so that may take a while. In the mean time, I did complete the re-cap before reading...
by TMAOne
Thu Feb 06, 2020 7:58 am
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Re: Does Anyone Recognize This Pattern?

Wow Mark, that was just the kind of precisely-targeted information I scarcely dared hope for. Thank-you! Unfortunately, I have not yet been successful in figuring out the two issues that happened after taking that picture, so I couldn't follow up right away. There were a total of 3 issues when I sta...
by TMAOne
Wed Feb 05, 2020 4:06 am
Forum: Hardware
Topic: Does Anyone Recognize This Pattern?
Replies: 15
Views: 5799

Does Anyone Recognize This Pattern?

Though I have been active in the ZX81 portion of this forum, I've not had a reason to post here before now. But recently while re-arranging scrap boards, parts, and whatnot, I came upon something I'd completely forgotten I had. 01.jpg 02.jpg It is an Issue 4A Spectrum 48K, picked up at a hamfest yea...
by TMAOne
Wed Jan 29, 2020 4:30 am
Forum: Hardware
Topic: Loading a program to my Minstrel 3
Replies: 19
Views: 3155

Re: Loading a program to my Minstrel 3

It's not often I disagree with Mark but as audio is my bag I would say this WAV is very mechanized ,lacking as it does the usual aural artifacts I think it's me you were disagreeing with Moggy, so Mark's reputation is intact. :) And I am confused. This is your test file. test_2020-01-28_21-59-08.jp...