Hi Mark,
Not sure where that has come from then as it was on the end of that capacitor and on the board too....
Russ
Search found 8 matches
- Wed Aug 08, 2018 1:34 am
- Forum: Hardware
- Topic: ZX Spectrum+ 128K Toastrack Repair
- Replies: 11
- Views: 7402
- Wed Aug 08, 2018 1:19 am
- Forum: Hardware
- Topic: ZX Spectrum+ 128K Toastrack Repair
- Replies: 11
- Views: 7402
Re: ZX Spectrum+ 128K Toastrack Repair
OK gents,
Had to put a hard wire in between pin 40 of the ULA and the emitter of TR6. Replaced the 100pf cap.
System now boots correctly and is happily running the diagnostic as well as the keyboard is fine....
Phew, sorted.... Never seen a leaking cap of that type before!
Russ
Had to put a hard wire in between pin 40 of the ULA and the emitter of TR6. Replaced the 100pf cap.
System now boots correctly and is happily running the diagnostic as well as the keyboard is fine....
Phew, sorted.... Never seen a leaking cap of that type before!
Russ
- Tue Aug 07, 2018 11:51 pm
- Forum: Hardware
- Topic: ZX Spectrum+ 128K Toastrack Repair
- Replies: 11
- Views: 7402
Re: ZX Spectrum+ 128K Toastrack Repair
Think I have found the problem! A cap next to the ULA looks like it has been leaking!!! https://s8.postimg.cc/orpbm0hhh/cap.png I think this is C129, can anyone confirm( I think the mask above is incorrect)? can any 100pf cap do? Looks like it has killed the track between TR6 emitter and ULA pin 40 ...
- Tue Aug 07, 2018 10:40 pm
- Forum: Hardware
- Topic: ZX Spectrum+ 128K Toastrack Repair
- Replies: 11
- Views: 7402
Re: ZX Spectrum+ 128K Toastrack Repair
Just checked the 5 connections to the ULA on the small KB1 and their associated pull up resistors and all seems OK.
No shorts between each other or earth either..
No shorts between each other or earth either..
- Tue Aug 07, 2018 10:23 pm
- Forum: Hardware
- Topic: ZX Spectrum+ 128K Toastrack Repair
- Replies: 11
- Views: 7402
Re: ZX Spectrum+ 128K Toastrack Repair
Thanks for the replies gents,
I get the same results with the new membrane, a 48k membrane and nothing attached.
I did notice the keyboard connector is loose but I buzzed it out with reference to the ULA and
all seemed fine. I will check both keyboard connectors again...
Russ
I get the same results with the new membrane, a 48k membrane and nothing attached.
I did notice the keyboard connector is loose but I buzzed it out with reference to the ULA and
all seemed fine. I will check both keyboard connectors again...
Russ
- Tue Aug 07, 2018 3:22 pm
- Forum: Hardware
- Topic: ZX Spectrum+ 128K Toastrack Repair
- Replies: 11
- Views: 7402
ZX Spectrum+ 128K Toastrack Repair
Ok gents, Looking for a little advice as I am quite a novice to fault finding on the 128K. ;) I had a 128K, issue 6K Toastrack that originally had a back screen with white lines and blocks on the paper. I found that the ROM (EEPROM) was faulty and replaced it with a new OTP 27C256. Now I get the fau...
- Wed Jun 01, 2016 12:31 am
- Forum: Welcome Area
- Topic: Another Newbie ish
- Replies: 1
- Views: 2178
Another Newbie ish
Hi All,
My name is Russ and I am a keen Sinclair hoarder!
Recently added a couple of TS1500s to my collection.
Thanks
My name is Russ and I am a keen Sinclair hoarder!
Recently added a couple of TS1500s to my collection.
Thanks
- Wed Jun 01, 2016 12:28 am
- Forum: WANTED
- Topic: Faulty ZX81
- Replies: 2
- Views: 3316
Re: Faulty ZX81
Mark,
I have a spare one, if you are only looking for the main unit?
It seems to be working OK apart from keys 1 - 5. Issue 3 mainboard.
Let me know if you are interested.
Russ
I have a spare one, if you are only looking for the main unit?
It seems to be working OK apart from keys 1 - 5. Issue 3 mainboard.
Let me know if you are interested.
Russ