Trump Card just £20 (but Project!)

[RWAP]

Does anyone want a Trump Card as a project for £20 plus postage?

It works most of the time - I have been struggling along with it for ages until a reasonable priced replacement came up (which I have now acquired).

So why is it a project?

Derek has tested and swapped some RAM chips. However, the card is still temperamental - sometimes the QL will freeze in the midst of copying files, and always seems to freeze if you use rename. I even had the QL turn on a couple of times without any keywords being recognised OTHER than the Toolkit II commands!

You will also need a WD1770 controller chip as I had to use the one from this Trump Card in my replacement unfortunately... I did have a WD1770 around here, but cannot lay my hands on it at the moment

[Derek_Stewart]

Hi Rich,

If no one wants the Trump Card, I will take it off your hands.

[RWAP]

Looks like Derek has already claimed it.

[1024MAK]

@ Derek

If / when you do solve the mystery, do let us know. It may be helpful to someone in the future

Mark

[Derek_Stewart]

Hi,

I will do my best.

I think that I tested all the DRAM Chips, logic Chips and replaced the Voltage Regulator, mabe the EPROM is faulty or a dry joint I missed.

I have another Trump v1 with no cover, which doubles as a heat sink, I was thinking about putting in a Traco TSR-1-2450 which the data sheet says it is a direct replacement for the 7805 Voltage Regulator.

I have put these in a QL, Spectrum and ZX81 and work really well, plus no heat sink required, so maybe the Traco TSR-1-2450 could be fitted and a plastic cover made.

[Derek_Stewart]

Hi,

I think the problem maybe down to the PAL chips, as the label on the PALs say: PAL1 & PAL2.

Where as another Trump Card I have the PALs are: 1V4 & 2V2, so my guess is that there was an update to the Trump Card v1 Pal Code.

I will buy some PAL16L8ANC chips and see if this solves the problem and report back.

[Derek_Stewart]

Hi,

The problem with the Trump Card is the through plating on the power regulator has detached from either side of the PCB.

The tracks could be repaired by soldering in wire links. But would be messy.

I have been reading about PCB repair. Where the through plating is replaced and soldered to the tracks on either side.

I will try this and see if the Trump Card works any better.