Issue 6 board updates

[Popopo]

I made several Issue 6 PCB clones.
For historical preservation.
I think not really to make the assembly this board, because of very rare original parts, such as the special serial, power, net connectors.

Actually I have bought one of your PCBs because I want to replace my Issue5 for a Issue6, or use to recover a QL whose board is already unusable, changing the pieces.
So I hope... your board will work

By the way... any news from your T1 and T2?
Any table to see specifications or differences?

Thank you for your job

[Popopo]

I made several Issue 6 PCB clones.
...
Possible, I need to make some replacement of this rare parts ?

Hi,
I bought a clone board to you, time ago. Nowadays I am building it up to transplant my components from my Iss5 to this one.
First problem... the schema about Iss6 that I have, doesn't match your clone.
What is happening with IC38? it is longer than is shown in the Service Manual that I have. Also there are not placed R93 and R94 that should where is part of your IC38.
Same about Ju1-Ju6

Before continue soldering more components, could you tell me or share the schema of this Iss6 version and the service manual?
To identify the components (watts, accuracy of resistors, etc).

Thank you

[Pr0f]

The service manual and circuit diagrams are posted on Dilwyn's site - which is mentioned earlier in the thread here.

If you get stuck the service manual is here - but I suspect the circuit diagram is not the corrected one:

https://www.sinclairql.net/srv/index.html

Most of the resistors can be 1/4 watt or 1/3 watt - accuracy of 5% or better - only for pull up / pull down they are not super critical.

Only the components around the PAL encoder chip are going to be fussy on type and value.

Diodes - I used IN4148 unless it was indicated otherwise, but any general purpose silicon diode will do for the keyboard matrix etc.

For the decoupling capacitors - 100n is fine - but some of them need to be axial because of board space issues and pad spacing.

[Popopo]

The service manual and circuit diagrams are posted on Dilwyn's site - which is mentioned earlier in the thread here.

If you get stuck the service manual is here - but I suspect the circuit diagram is not the corrected one:

https://www.sinclairql.net/srv/index.html

Most of the resistors can be 1/4 watt or 1/3 watt - accuracy of 5% or better - only for pull up / pull down they are not super critical.

Only the components around the PAL encoder chip are going to be fussy on type and value.

Diodes - I used IN4148 unless it was indicated otherwise, but any general purpose silicon diode will do for the keyboard matrix etc.

For the decoupling capacitors - 100n is fine - but some of them need to be axial because of board space issues and pad spacing.

Thank you for your answer,
Exactly about circuit diagram in Dilwyn's site. I just discovered it last night that there were different Issues 6 (pre and post at least) versions. Later it seems to appear the right diagram (manual service) with some notes that match this board from Tetroid, but... I am new in this Sinclair QL World, so no idea if that is right or not.

Neither differences among those boards.
BTW, Where to get the Gal file to program it? Cause I have not this chip in my QL Issue5.
Axial capacitors... OK, I will remember it depending on place. In some problematic case... I could use SMD capacitors with some adapter.
Did you build your board up?

I am taking notes about all the components to put it in a file (table) and to share. But now, how I don't know what I have (board version)... no idea what to write it on.

[Pr0f]

The board I built was Tetroid's successor to the Issue 6 - it was a T1 board I think he called it. There were changes to the power supply, and the area around the modulator - and it came with 9 pin D connector footprints instead of those strange BT and Reverse BT plugs.

It's working now - but I had a few teething problems with it.

The HAL chip on the issue 6 can be replaced by a programmed GAL - there is a post on the forum here with the logic required to program it.

viewtopic.php?p=36218&hilit=HAL+chip#p36218

I have an Issue 7 board as well - and both boards have Tetroid's ROM switcher so I can have a choice of ROM Images.

[Popopo]

Thank you!

Amazing, I didn't know about all those versions (but T1 that he explained here that had some problems).
Such a pity That he didn't wrote down on board the Issue version in particular.

Well... I will write him directly. Perhaps, he tells me what version is it or list part of components.

Cheers

[Pr0f]

Issue 6 is this board:

https://th.bing.com/th/id/R.2ca6727bc7b ... ImgRaw&r=0

The T1 board (Tx - I think he planned more than 1) is here:

https://th.bing.com/th/id/R.dcd58db3846 ... ImgRaw&r=0

Note issue number is shown on the silkscreen layer

[Popopo]

Issue 6 is this board:

https://th.bing.com/th/id/R.2ca6727bc7b ... ImgRaw&r=0

The T1 board (Tx - I think he planned more than 1) is here:

https://th.bing.com/th/id/R.dcd58db3846 ... ImgRaw&r=0

Note issue number is shown on the silkscreen layer

Thank you,
Sorry, I mean the user manual & maintenance manual for the Iss6 board that Tetroid sells (and I got).

[Popopo]

Hi again!
Mounting the board Issuue6... I am doubting about type of capacitor to use for C27, C28... DC1-DC29, they are about 35 all.
The manual says they are 0.1uF 50V, -20%+80%, what I have not clear... is... which type of capacitor should I set into?.


This image shows the capacitors settled in one board:


And those are the 3 options that I could get:





I am not sure about differences between them and what could be the best option.

Thank you

[Pr0f]

These capacitors labelled DCn (where n is some number) - are generally 100nF decoupling capacitors - any good quality 100n capacitor will do - but if you want to maintain the look and clearance of the original board - try and find the axial ones (wires sticking out either side of a cylinder). Voltage rating - 50v should be more than enough, but higher is no problem - size and clearance are the key things here.