BT Cheetah similar to LO3000 - Repairing.

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M1ECY
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Re: BT Cheetah similar to LO3000 - Repairing.

#11

Beitrag: # 6898Beitrag M1ECY »

Hi Patrick,

Yes, I hope the same.

It will be interesting to see if the CPU cards in the Lo3000 are the same as in the Cheetah.

I might be able to source a replacement processor, but I am hesitant to order parts until I have a better idea of what is going on.

Do you know if there were extender cards made for the Lo3000, to allow tests to be carried out on the boards?

Sean
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Patrick
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Re: BT Cheetah similar to LO3000 - Repairing.

#12

Beitrag: # 6899Beitrag Patrick »

Hi Sean,
I'm not aware of any extender cards. Would be helpful to build one to get better access to measure. The connectors are standard parts which should be easily available. Which supplier do you have in the UK (except RS) ?
Patrick
i-telex:
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b.) T1200SD : 465111 vfw d

i-telex (mobile Anlage):
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Topic author
M1ECY
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Re: BT Cheetah similar to LO3000 - Repairing.

#13

Beitrag: # 6901Beitrag M1ECY »

Yes, I think I can source the connectors - will take a look, and make a set of extenders up.

Think there may be an order with Richelt about to happen - they are better value than RS!
669089 Siemen G - T100S Online 24H
299709 Antosh G - Creed 444 - Double Current R + D (0800 - 2100) and a bit tempremental
459724 NC
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Topic author
M1ECY
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Re: BT Cheetah similar to LO3000 - Repairing.

#14

Beitrag: # 6902Beitrag M1ECY »

Connectors ordered - will make up a pair of extender cards.

Now on the hunt for a processor - this one is dead.

Sean
669089 Siemen G - T100S Online 24H
299709 Antosh G - Creed 444 - Double Current R + D (0800 - 2100) and a bit tempremental
459724 NC
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Topic author
M1ECY
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Re: BT Cheetah similar to LO3000 - Repairing.

#15

Beitrag: # 6931Beitrag M1ECY »

I have now made the extender cards, this will make checking the boards in circuit so much easier.

Luckily, there was a good supply of Eurocard connectors on eBay UK.

I have found a UK source of spare processors, so one is on order.
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669089 Siemen G - T100S Online 24H
299709 Antosh G - Creed 444 - Double Current R + D (0800 - 2100) and a bit tempremental
459724 NC
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Topic author
M1ECY
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Registriert: Fr 11. Aug 2017, 13:13
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Re: BT Cheetah similar to LO3000 - Repairing.

#16

Beitrag: # 6935Beitrag M1ECY »

A couple so pics of the story so far
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669089 Siemen G - T100S Online 24H
299709 Antosh G - Creed 444 - Double Current R + D (0800 - 2100) and a bit tempremental
459724 NC
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Topic author
M1ECY
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Re: BT Cheetah similar to LO3000 - Repairing.

#17

Beitrag: # 6958Beitrag M1ECY »

Work carries on slowly.

I have replaced the processor on the CPU board, now the green status LED is illuminating again.

I also traced a bad 74s04 chip on the smaller board that sits behind the CPU - this was replaced with a 74LS04 that I had laying in stock.

A couple of times this evening the bell sounded in the machine, and the screen rubbish changed, but nothing else has happened.

Awaiting a logic probe to have a look around the CPU to find out what is going on.
669089 Siemen G - T100S Online 24H
299709 Antosh G - Creed 444 - Double Current R + D (0800 - 2100) and a bit tempremental
459724 NC
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Patrick
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Re: BT Cheetah similar to LO3000 - Repairing.

#18

Beitrag: # 7494Beitrag Patrick »

Hi Sean
attached is the content of the M2716 EPROM on the CPU board for testing, hope this helps for the start (it also contains the telex number). I think that's the CDP (customer data prom) and there is not much in it. Changes are programmed into this eprom as well (using a configuration plug). I've never tried it before but it is an old loudspeaker connector as we have used them many years ago.

Regards
Patrick
Du hast keine ausreichende Berechtigung, um die Dateianhänge dieses Beitrags anzusehen.
i-telex:
a.) T1000S : 54577 aros d
b.) T1200SD : 465111 vfw d

i-telex (mobile Anlage):
11113 t68d 1-Streifen-Maschine
7826519 t68d 2-Streifen-Maschine

piTelex Test - aktuell offline
T1000S : 183282 isoph d
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Topic author
M1ECY
Rank 7
Rank 7
Beiträge: 686
Registriert: Fr 11. Aug 2017, 13:13
Wohnort: Hitchin Hertfordshire, UK
Hauptanschluß: 669089

Re: BT Cheetah similar to LO3000 - Repairing.

#19

Beitrag: # 7498Beitrag M1ECY »

Thanks Patrick, I will get a new eprom blown, and see if this helps the machine to do something.
669089 Siemen G - T100S Online 24H
299709 Antosh G - Creed 444 - Double Current R + D (0800 - 2100) and a bit tempremental
459724 NC
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