Newbie - info on Spectrum 16k Series 1

[hanger312]

Hello, I've purchased and await delivery of a Series 1 ZX Spectrum 16k
with blue keys.

The box has the 16k sticker on as does a small circular sticker on the back.
The sticker on the back partially covers the top middle screw which suggests it is an original. I do see series 1 cases for sale on ebay.

Does anyone have a picture of the mother board as it should be or provide a link because I can't seem to find one?

Any tips on how to test it is a 16k model? Is is a rare item with the blue keys as I understand the blue keys were introduced after the grey keys very shortly before the 48 model came out with the same blue keys.
Thanks in advance. Reliving my youth. Ex ZX81, Speccy, C64.

[drdivago]

Hi,

This is just one of many images you can find: https://spectrumforeveryone.com/wp-cont ... ssue-1.jpg

Please do note this photo includes the 32K expansion, which should be missing in your case.

Ciao
Leo

[Turtle_Quality]

"Any tips on how to test it is a 16k model?"

If it's in working condition, the obvious way is

POKE 32768,42
PRINT PEEK 32768

[TMD2003]

"Any tips on how to test it is a 16k model?"

If it's in working condition, the obvious way is

POKE 32768,42
PRINT PEEK 32768

Or, better still, using a memory address that actually means something to the system: PRINT PEEK 23733 - returns 127 for a 16K Spectrum or 255 for any other Spectrum. Technically, it's the high byte of P_RAMT which stores the address of the highest byte available to all of memory (32767 for 16K, 65535 for 48K).

Turtle_Quality's test returns 255 despite poking a value to 32768, solely because the 16K Spectrum can't read an address that isn't there.

[hanger312]

Thanks guys. Still waiting. Coming by Royal Snail.

[hatman72]

If the case has not been opened, how do you know it is an issue 1 board? I suspect the serial number starts with 001, but that does not make it an issue 1, more likely to be an issue 2 board.

[hanger312]

ok - I'm still waiting on Royal Snail. It was sent 2nd class post so God help me I get it soon! Seen pics of series 1 boards with the writing ethced. Here's hoping. I don't really want to open it unless it isn't working.

[spider]

You might gain some insight by just looking through the edge connector opening, although I've not seen a "look through here" picture of an Issue1 that way, I'm thinking with a bright light you might be able to see a few things to determine if it is or not.

[drdivago]

There you go, the link to a snapshot of an Issue 1 from the back

https://1drv.ms/u/s!As1H_JFb9yqcyj_txmg ... g?e=msTW16

[hanger312]

Thanks for that. Got the image.

[Hedge1970]

For me personally the issue 1 board is what makes these machines interesting. It’s the “visibly” hand drawn circuit board that defines a point in time when a computer was still very much hand made. It’s this aspect that I find interesting. The fawn keyboard is “special” because like with so many collectible items it was not fit for purpose. It did not offer enough contrast for users to be able to see the multi function writing on each key, it also wore out too quickly and showed/picked up dirt off of grubby teenage fingers too easily. Which is why the more common blue keyboard was rolled out across the model. In addition to its sub par keyboard the cooling system was poor, incorrectly placed and too small led to that being upgraded. Finally the electronics were flawed and from factory were modded. Not all mods the same and not all modded from day one. This leads into one of the other much talked about “issue 1” topics, issue 1 board and case with blue keyboard. Now the board as discussed was hand drawn, but this was not the only manual part to the Speccy story. As the first systems made were shipped and many would be RMA’d for various reasons. As mentioned above the original faun keyboard was a poor design colour and so some of these RMA’d machines would be upgraded not only by modding the electronics - “the cockroach” but also upgrading the keyboard for free! In addition to this as has been speculated due to rumours that NIB issue 1 speccys had the blue keyboard, there was a great demand for the Speccy and so all parts available would be put to use. As issue 2 boards came into production a few issue 1s were finished off with the new stock parts.

So in short Issue 1s had poor electronics, poor cooling and a hard to read keyboard. Like all of life’s great failures it makes them quite the collector items now. However for me it’s the circuit board that made me get one. I’ll never run it for all the reason stated here. It’s for good reason that the circuit boards in the 16/48k machines made it to Issue 6, arguably they ironed out all the major issues by 3b and then just optimised. Either way an Issue 1 board is not suitable for running, if you got cash to burn then just think of the historical value that you could trash by using it, give it away to a museum or sell it cheap to someone who will look after it.

I hope it arrived safely and that you appreciate the history in your hands.

[KWF]

Congratulations with the purchase. Personally I was not able to justify spending silly money on Issue One, so I cloned it a few years ago. It was a challenge because I had to do all tracks manually with no access to real one and using photos available on various websites and with a help of a few good souls.

[hanger312]

Thanks for the comprehensive replies. Much appreciated. Reliving my youth. The 001 16k Spectru, arrived. Unfortunately it is a series 2 board. Did video mod. Checked border colors on screen and it was flickering from b&w to colour. It's not b&w only. Changed the membrane (original snapped and bits stuck in the connectors . All good so far except the colour issue. Stress tested by leaving on a while and no probs.

[drdivago]

Check the voltages, 12V are needed for the video section to work properly.

This one being an Issue 2, another possibility is that potentiometers VR1 and VR2 need to be adjusted.

Ciao
Leo

[hanger312]

Thanks for that. I will check. Not been on the forum for a few days.