anyone here any good with vintage computer repair

[ninogenio]

hi there my spectrum 128k +2 seems to have developed a problem it was working perfect last time i used it about 6 months ago but just today i went to break it out for a bit of fun and it wasnt reading my tapes it was just blank with the tape turning so i just let it keep playing through the tape rewinding and fast forwarding after a while it started picking data up again although roughly so i kept playing and eventually it worked fine. then went to mess around tonight and the same.

its as though when the drive is cold it doesnt pick any thing up and once it warms up a bit it starts to work again. i was just wondering if anyone had any knowledge of old tape drives and what parts might cause this problem thanks.

[Clyde]

if you play your game tapes in a regular tape deck do you hear any of the infamous data noises?

[Jim]

I remember opening up the +2 and soldering on a headphone socket I got from Tandy so I could use an external cassette player.  The original was really unreliable even when it was new

If you feel like tinkering, there's a screw on the playback head which you can get at at the front, called the azimuth head alignment.  Try giving it a half turn or so in each direction to see if you can get a better alignment.  That might help, or not, so try to remember the original position of the screw!

Jim

[ninogenio]

@clyde the +2 doesnt have an external tape adapter on the back as i guess amstrad thought the internal tape deck was all that folks would need

@jim earlier today once i started getting data picked up by the head i adjusted the azimuth to the best alignment but then the problem come back tonight the problem seems to only be existent when the drive is cold im thinking it must be something that has worn with age. i also cleaned the heads reall well to make sure there was no oxidisation.

guess i will have to open it up to have a closer look at the band and things.

btw your headphone socket mod you did was it easy enough i would love to be able to use the laptop to transfer files back and forth through an audio lead but not sure if it would work.

im sort of ok as i have a divide but you cant save through it.

[Clyde]

I was thinking that if you play your game casette in your hifi's tape deck, and you can hear the loading noises, you could tell wether or not your tape(s) has been wiped.

[ninogenio]

ah sorry mate i misread your initial post the tapes are fine and do load in the spectrum but only after about half and hour of play fast forward rewind punch then it starts working perfect.

once it gets going it loads everything first time so i dont really understand whats going on with it tbh.

[Jim]

It took a few minutes to solder the two wires once the case was open. 
You might be able to find some information on how to do it on WOS
I found a photo of the circuit board with the colours of the wires mapped to what signals they carry somewhere on here

Either your problem is mechanical - the motor/rubber bands take a little time to grip - you could try replacing them with rubber bands, or it's electrical - some capacitors are taking a while to warm up.  If you just leave the machine powered on for an hour before you start do you still need to fast forward/rewind the tapes?

Jim

[ninogenio]

hey jim,

thanks for all that info. i left it on for around 2 hours last night till the specci was really warm and tried but still nothing. i did notice every maybe quarter second of the tape being played there is a clicking noise coming from inside the tape drive and if i press fastfarward the clicking noise happens so frequent that its almost in audiable i dont know if its normal so im going to have to go in and see whats going on.

if i dont have any joy with getting the drive going im going to try attach a earphone socket using the diagram from that link. i take it its just the two wires that normally go to the head one for reading and one for writing left and right channels from a stereo source?.

[Jim]

It's not stereo, so one lead goes to ground, the other goes to the EAR connection - for stereo connect both L and R to EAR.

Jim

[ninogenio]

ah i see thanks jim.

well im going to have a play later so fingers crossed

[Jim]

Oh, and you said ....wires that normally go to the head.... but you definitely don't want to wire anything in at that point - the read head is really sensitive and the tiny voltages from that are fed in to the circuitboard on the cassette deck and pre-amped before they go the the main board.  So that is the point, at the main board, where you want to solder your wire.

Jim

[ninogenio]

cheers for that jim k+ you probably saved me making a big mistake.

i looked at the schematics for the +2 and wired acording to them where pin 1 and 5 are negative pin 2 is mic 4 is ear and 3 is +5v.

so i soldered on to 1 and 4 on board. now im not sure if ive done it right but i couldnt get anything to load on specci i was yousing winamp tap plugin and trying all different graphic equ settings but most i got at one point was the boarder to change to red. plenty of data sound coming through the tv though.

when i took the lead out of the headphone socket on the laptop though and pluged it into the the mic socket. using windows recorder i was able to record stuff from the specci to the pc no problems.

do you think i might have soldered on to the mic channel instead of the ear? or would soldering onto the ear allow recording and playing.

if i have soldered on to the mic by mistake can i just add another socket to the ear to allow saving and recording.

cheers for the help so far btw.

edit - just realised that i probably have soldered onto pin 5 thinking it was 1 and that would mean i have indeed conected to the mic giving myself the exact same functionality as the sound socket on the back   doh

[ninogenio]

further update i discovered for some reason on my spectrum the mic and ear on the casset plug have to both be conected to the ear socket(i think this is because the loading sound going through the mic chanel when conected to the ear basically acts like a bit of an amp. the other problem was that my laptop and mostly every thing with eu legislations over here mp3's etc are just not loud enough for the specci. so i pluged it in the hifi gave it some good power and it worked! its pretty cool now that i can get external sources to work. hopefully my psp without volume limiting will work it too not tried yet.

if any one else want to do something similar here is the wire colors on the specci +2 tape plug.

black and brown negative.
white mic.
red +5v for drive mech and power light.
blue ear.

cheers so much jim i was going to throw it back in the cupboard and buy another one but no need now!.