TrumpCard modification
TrumpCard modification
Recently I heard about an useful modification for some TrumpCard models. It promises to prevent heat and improve stability.
I tried some search but with no results. Unfortunately my information are defective: it should be something about adding a resistor on the top-right angle of the board, but I don't know exactly which kind of mod is it.
Could anyone help me please to understand if my Trumpcard needs this mod or not please? How can I exactly identify my board model? Does it need some further modification?
I tried some search but with no results. Unfortunately my information are defective: it should be something about adding a resistor on the top-right angle of the board, but I don't know exactly which kind of mod is it.
Could anyone help me please to understand if my Trumpcard needs this mod or not please? How can I exactly identify my board model? Does it need some further modification?
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- Font of All Knowledge
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Re: TrumpCard modification
Hi,
You could replace the 7805 voltage regulator with a TSR 1-2450 which is a drop replacement for the 7805. With the advantage of no heat.
I have fitted them to QoLs, Spectrums ZX81s etc all wlork a lot cooler.
The QL conversion does away with the heat sink, makes the microdrive run cooler.
You could replace the 7805 voltage regulator with a TSR 1-2450 which is a drop replacement for the 7805. With the advantage of no heat.
I have fitted them to QoLs, Spectrums ZX81s etc all wlork a lot cooler.
The QL conversion does away with the heat sink, makes the microdrive run cooler.
Regards,
Derek
Derek
Re: TrumpCard modification
Thank you very much for you important informationDerek_Stewart wrote:Hi,
You could replace the 7805 voltage regulator with a TSR 1-2450 which is a drop replacement for the 7805. With the advantage of no heat.
Anyway, even if I'm almost sure mine is not the so-called TrumpCard2, on the other hand some questions still remain...
I couldn't find the article talking about the top-right resistor modification, but I found an old ad (September 1990) presenting the "new" TrumpCard (please see below).
So my confusion has increased
Could anyone help to identify my 768K board model please?
- XorA
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Re: TrumpCard modification
A quick look at google and it appears Trumpcard 2 says Trump Card 2 in giant letters in the space saved by only having 6 ram chips
- janbredenbeek
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Re: TrumpCard modification
You probably meant this picture:XorA wrote:A quick look at google and it appears Trumpcard 2 says Trump Card 2 in giant letters in the space saved by only having 6 ram chips
The 6 RAM chips are actually M541256 ones with 256K x 4 bit each. Cristian's card is the original one with 24 x 256Kbit RAM chips.
Jan.
Re: TrumpCard modification
Yes I do know the TC2 an this is the reason why I told I'm sure it's not mine.XorA wrote:A quick look at google and it appears Trumpcard 2 says Trump Card 2 in giant letters in the space saved by only having 6 ram chips
Let's focus to the real questions:
1) Was the ad talking about the TC2 or...?
3) How many 768K versions do exist and which model is in my possess?
Re: TrumpCard modification
[quote="jCristian's card is the original one with 24 x 256Kbit RAM chips.
Jan.[/quote]
Do you mean the very first model?
Jan.[/quote]
Do you mean the very first model?
- XorA
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Re: TrumpCard modification
256K x 4 bit is 1 megabit so its talking about the TC2Cristian wrote:Yes I do know the TC2 an this is the reason why I told I'm sure it's not mine.XorA wrote:A quick look at google and it appears Trumpcard 2 says Trump Card 2 in giant letters in the space saved by only having 6 ram chips
Let's focus to the real questions:
1) Was the ad talking about the TC2 or...?
3) How many 768K versions do exist and which model is in my possess?
You have the original! (of which there maybe minor revs but one of the experts will have to comment on that).
- janbredenbeek
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Re: TrumpCard modification
Yes, but the RAM chips are really 4 bit ones. There's a circuit diagram in the same directory (http://gigant.chem.elte.hu/ZXSpectrum/QL_Trump_Card/) where the picture resides and that clearly shows each chip has 4 data lines.XorA wrote: 256K x 4 bit is 1 megabit so its talking about the TC2
I guess the V2 Trump Cards are very rare. By 1991 the Gold Card was introduced and Miracle Systems had a trade-in offer for Trump Card owners. I still have the invoice (I got GBP 80.59 back from GBP 291.18 - weird looking numbers but I bought it cash with Dutch Guilders at an Eindhoven meeting).You have the original! (of which there maybe minor revs but one of the experts will have to comment on that).
Jan.
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Re: TrumpCard modification
That still makes 1 megabit, so I am a little confused what you mean!janbredenbeek wrote:Yes, but the RAM chips are really 4 bit ones. There's a circuit diagram in the same directory (http://gigant.chem.elte.hu/ZXSpectrum/QL_Trump_Card/) where the picture resides and that clearly shows each chip has 4 data lines.XorA wrote: 256K x 4 bit is 1 megabit so its talking about the TC2