Search found 624 matches

by Pr0f
Sun Jul 12, 2020 9:49 pm
Forum: Hardware
Topic: qubide single ended version what gal version ?
Replies: 9
Views: 922

Re: qubide single ended version what gal version ?

if the other chips are all through hole, then this is the same version I have built - only those 646 chips are surface mount - one on one side and one on the other side of the pcb
by Pr0f
Sun Jul 12, 2020 6:24 pm
Forum: Hardware
Topic: qubide single ended version what gal version ?
Replies: 9
Views: 922

Re: qubide single ended version what gal version ?

the 74hct646 should be available on ebay - for 2 off quantities.

Do you have something like festo / RS / Farnell there?

Also - does the version you are building have the surface mount version or the dip version of this chip?
by Pr0f
Sun Jul 12, 2020 8:55 am
Forum: Hardware
Topic: QL speaker
Replies: 10
Views: 844

Re: QL speaker

the speaker is normally driven via a pnp transistor and an 82R resistor, so you should be ok to test it with a 100R resistor in series with the speaker and a 5v supply. You should leave one end of the resistor / speaker free, and just dab it on the supply - you should hear crackling sound. The other...
by Pr0f
Sun Jul 05, 2020 7:58 am
Forum: Hardware
Topic: QL speaker
Replies: 10
Views: 844

Re: QL speaker

a regular QL breaker !

I had an issue 7 board from him which is now housed in a case that contained a somewhat broken and heavily modded (internal ram upgrade -several dead chips, broken tracks, failed ic's). The issue 7 board is working great :-)
by Pr0f
Sat Jul 04, 2020 2:42 pm
Forum: General QL Chat
Topic: Key matrix positions
Replies: 3
Views: 563

Re: Key matrix positions

The other piece of you puzzle can be found in the aurora manual - as it gives the key tails positions to IPC pin row and colum definitions

http://www.dilwyn.me.uk/docs/manuals/aman2.pdf
by Pr0f
Sat Jul 04, 2020 2:37 pm
Forum: General QL Chat
Topic: Key matrix positions
Replies: 3
Views: 563

Re: Key matrix positions

by Pr0f
Fri Jul 03, 2020 9:05 am
Forum: Feedback Section
Topic: Tetroid.
Replies: 7
Views: 4551

Re: Tetroid.

Given he lives in the outlying regions, it's not suprising it takes a while - but I have to say I have several products from Tetroid - and all have been packed really well, documentation included to get you going, and the boards themselves are excellent build quality.

Top Marks! :D
by Pr0f
Mon Jun 29, 2020 2:28 pm
Forum: Hardware
Topic: QL-SD
Replies: 52
Views: 3624

Re: QL-SD

A lot depends on the type of socket used - push instert / push eject are the best, as it's a positive action for both operations, and I believe the socket has a switch to give 'card present' when inserted. Even someone with stubby fingers like me can get a microSD out of one of those sockets. There ...
by Pr0f
Mon Jun 29, 2020 10:59 am
Forum: Hardware
Topic: Aurora somewhere?
Replies: 51
Views: 14039

Re: Aurora somewhere?

gorlum wrote:Who can put a photo of the Aurora on the side of the tracks?


It looks like a 4 layer board - so that probably won't get you very far.
by Pr0f
Sat Jun 27, 2020 8:48 am
Forum: Hardware
Topic: Issue 6 VM12 & resistors confusion
Replies: 79
Views: 4337

Re: Issue 6 VM12 & resistors confusion

I'd second what Tobias says, a new keyboard. Repairs? - even a small amount of silver conductive paint doesn't hold up for long. I just replaced one keyboard where it had failed on the bend where the keyboard tail tucks behind the metal backing plate - this is such a tight turn - the plastic had gon...