Improving Timex/Sinclair Tape Loading

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1024MAK
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Re: Improving Timex/Sinclair Tape Loading

Post by 1024MAK »

Lardo Boffin wrote: Fri Dec 08, 2017 10:26 am Excellent! Having had some experience of fixing tracks I have broken ( :oops: ) I suspect it will be no problem to sort. 8-)
I spy some very close together pads, so it would be a good idea to make sure that any that are not supposed to be connected, aren't actually connected.

And yes, soldering a piece of solid core wire over a break or crack on a new PCB is rather easier than overcoming track damage on an old densely packed commercial PCB. Clean the track and quickly and carefully "tin" it. Then where possible, either leave a component lead (like a resistor or capacitor) long and bend over, or use an off-cut of a component lead ;)

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

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Re: Improving Timex/Sinclair Tape Loading

Post by Lardo Boffin »

Now to find the time to assemble it!

E4518690-1EAF-482B-93BB-1C6EF1B24A1D.jpeg
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Thanks sir morris!

Doubtless some questions to follow about polarity of components and which wire goes where...
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Dim_75
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Re: Improving Timex/Sinclair Tape Loading

Post by Dim_75 »

Great !!! :D If only i had enought time to do so.
Good work
Lardo Boffin
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Re: Improving Timex/Sinclair Tape Loading

Post by Lardo Boffin »

Where can I get a cheap switch from? The connectors on the ones I have are way too big to fit the small holes. :shock:
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
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Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
sirmorris
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Re: Improving Timex/Sinclair Tape Loading

Post by sirmorris »

I expected wire flying leads from the board to the switch as it was highly unlikely that the switch you had would have fitted the layout I had. This would also make putting the lil fella in a case easier as you would have free rein on the switch placement. You might consider putting the LED on wires too - for the same reason. Do you have any heat shrink tube?
Lardo Boffin
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Re: Improving Timex/Sinclair Tape Loading

Post by Lardo Boffin »

sirmorris wrote: Sat Dec 23, 2017 7:28 am I expected wire flying leads from the board to the switch as it was highly unlikely that the switch you had would have fitted the layout I had. This would also make putting the lil fella in a case easier as you would have free rein on the switch placement. You might consider putting the LED on wires too - for the same reason. Do you have any heat shrink tube?
That would make sense! :D I don’t have any heat shrink tube (or an appropriate source of heat) so will improv with normal insulated wire.

Just got to order two resistors and am ready to build. :shock:
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
Lardo Boffin
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Re: Improving Timex/Sinclair Tape Loading

Post by Lardo Boffin »

Finally got started! :roll:

3DE6371F-0412-49FC-AAD1-E42FB4ABED6F.jpeg
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Assuming the picture shows correctly orientated (layout to left and board to right):-

Does the IC go in notch upwards?
Does it matter which way the LED goes in (i.e. polarity before any aussie themed replies appear...)?
Which way does the diode go in? Stripe at the ‘top’?
Does the positive of the battery holder connect to the + on the reverse of the board?
Which part of the cassette cable connects to S and which to G? I assume the tip is S and the ‘sleeve’ is G.
I assume it doesn’t matter which way round the switch goes?
Do I need to do anything with GND?
Finally (!!!) what are the two holes for at the bottom of the board?

:D
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
Lardo Boffin
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Re: Improving Timex/Sinclair Tape Loading

Post by Lardo Boffin »

So some very necessary reading / learning later...

Yes an LED is polarised (light emitting DIODE). Clue was in the name I guess. It looks like the longer leg should be positive but it appears I can check this with the diode test setting of a multi-meter.

Looking at various wiring diagrams for mono plugs does suggest the tip is S and the jacket is G so I will go with that.
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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TMAOne
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Re: Improving Timex/Sinclair Tape Loading

Post by TMAOne »

That's a nice looking board you're working on Lardo--much better than my cobbled together effort. I'm excited for you.

You've answered most of your own questions. Refer to the circuit diagram for the rest, as "top" is somewhat arbitrary.

The stripe on the diode goes where the "line" is on the circuit diagram. (I think of the symbol as depicting an "arrow" hitting a "wall", showing the direction in which current can NOT flow.)

Looks like you're almost there,...
Ian
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1024MAK
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Re: Improving Timex/Sinclair Tape Loading

Post by 1024MAK »

Diodes (and LEDs):-
Image
Image

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
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