Want to resurrect your D/D2 MAC kit?

[Channel Hopper]

Welcome aboard.

 

[PaulR]

Welcome to the forum Phil.

Yes, you'll find all sorts of curiosities and fossils (thread subjects - not the members!) here as well as the usual modern stuff.

 

[Captain Jack]

Received my encoder...

Anyone have any information on this particular chip? Cannot find anything on the interweb... @Vipersan ?

 

[s-band]

Received my encoder...

Anyone have any information on this particular chip? Cannot find anything on the interweb... ?

Did you mean the Harris/Intersil one? HA3-2539-5 IC OPAMP 600MHZ 600V/US 14-DIP Intersil datasheet pdf data sheet FREE from datasheetz.com

The filter looks more like a module (thick film?) than a chip

 

[Captain Jack]

Ah, sorry, should have clarified. The big UMHLS800 one. Ideally with a pin-out diagram...

 

[Channel Hopper]

Matthey printed Products of Stoke on Trent. Haven't heard that name for at least 20 years

 

[scopus]

Matthey printed Products of Stoke on Trent. Haven't heard that name for at least 20 years

Yes, long gone...

 

[Captain Jack]

Dug this beauty out. This is the later model of the Philips FilmNet BBD-901 decoder - looks exactly the same but this one has been castrated of its second SCART socket along with a number of cinch connectors. This does come with a remote though...



Edit: this is the decoder - I must have had a 900 version. Philips FilmNet BBD-901 d2mac decoder FAQ page

I remember having the problem with picture shifts and coloured tints...

 

[Analoguesat]

And now you can build an analogue transmitter using sdr!

Analog TV Broadcast of the new Age

 

[Captain Jack]

Generate PAL, encode in DMAC, transmit, receive with an old receiver with an attached DMAC decoder - watch... [emoji38]

 

[fsphil]

The image parts are simple enough to do, the digital bits are more interesting!

 

[fsphil]

Digging myself further into this hole, I've now got a receiver too. A Philips STU 902/05R which powers up nicely but the remote is a bit iffy. Not coming with a manual I was hoping someone here knows more about them. Do they have a tuning menu that I'm missing? It has 10 channels but I don't know what IF frequency it expects for each one. There is a Setup switch on the rear which lets me see the signal (well, static at the moment) but in that mode all I can do is change the channel.

 

[fsphil]

In case anyone is interested, after a bit of playing about with test signals and googling the frequencies used, I've made this list:

1: 12.09190 The Movie Channel
2: 11.93846 The Sports Channel
3: 11.86174 Galaxy
4: 12.01518 The Power Station
5: 11.78502 Now
6: 11.74666 ?
7: 11.82338 ?
8: 11.90010 ?
9: 11.97682 ?
10: 12.05354 ?

 

[Captain Jack]

You can't do it like that with these modulators as it outputs the MAC signal only, not RF modulated. It basically outputs what your non-MAC receiver would pump out of its SCART socket to the decoder.

That said, these BSB receivers have been widely modified to accept an input from the receiver so there's a way ... but I don't have the instructions for doing this. Perhaps someone does?

 

[s-band]

I think that the BSB LO frequency was 10770MHz so that will give you the frequencies that you need to feed to the STB. Don't forget the DC break to stop the LNB supply killing what ever you connect it to. You may be able to find an analogue 1.3GHz ham TV transmitter that covers the IF band if you are lucky. Unless you can find the modification info, I think that you are stuck with fixed frequencies. If you want a tuneable Ferguson box, modified for D2 MAC, I'm sure I had one somewhere

Edit: I measured a NoS BSB LNB and it's LO is 10760.9MHz so it may have started life at 10770

Edit 2: I found an X2402 EEPROM from that era which may have been loaded with D2MAC mod code for either a Ferguson or Philips box. OTOH, it could be blank or original firmware. If anyone wants it, PM me.

 

[fsphil]

I'm using an SDR (hackrf) to transmit to the receiver, but for now it's just an unmodulated carrier. That's enough for me to see if I got the frequencies correct at least.

The next step will be to capture the output from the test card generator, and replay that to the receiver. From what I've read the bandwidth of these signals was 27MHz which is a bit much for the hackrf, so that might cause problems.

 

[Captain Jack]

That's very interesting.

@fsphil are you going to try to splice real video signal into the MAC generator? I haven't looked in any great detail on mine but I think I isolated the part of the board that encodes the pattern generator into MAC. Need to probe a little!

 

[Channel Hopper]

I've got nothing left in terms of D/D2 MAC circuit design, modification, test patterns and component parts - which was for warranty transfer to the UK and to update the UST 92 from a FTA box to the subscriber card version - when Uniden closed it's doors (1993 ?) everything was collected up from the office and destroyed, as per the contractual requirement.

 

[Captain Jack]

D2MAC decoder in action:

 

[Captain Jack]

I remember that Viaccess and Eurocrypt cards were similar and could be read in either box, so I put in my old Fransat card in....