Alfaglade Churchill D2Mac inside view

Churchill & Optimac D2Mac satellite TV decoder FAQ

1. The Churchill power supply is similar to the Pace PRD type.
A repair kit is available from SatCure (see Products section).
A power supply that whistles is about to fail! Disconnect the power cord and do not reconnect it until the unit has been repaired. At this stage you can probably fix it simply by fitting three capacitors. I'll send these to you if you post me four unused 26p stamps with your request :o).
DO NOT REPLACE THE FUSE! It is there to protect YOU and the receiver. If you replace it you can make any damage worse and put yourself at risk!

2. The Optimac power supply uses a transformer which is available from SatCure.

***PLEASE CHECK SatCure ORDER FORM for latest prices***

3. The main problems with the Churchill are bad connections or corrosion in the IC sockets.
PLCC extractor toolA special extractor tool is available from SatCure for the square chips.

The chips *can* and do fail but fault-finding is usually a complicated business.
In order of likelihood, you could try replacing the following chips:

DMA2286 price £26.86 or use a DMA2285 price £8.00
DMA2281 price £24.48 or use a DMA2280 price £8.00
CCU3000 price £8.35

SatCure can test the Eprom for you for just the cost of postage £2.50.

4. The Remote Control Handset is available from SatCure.
The same remote operates both Churchill and Optimac decoders but note that many Optimacs had NO remote sensor fitted inside. I can supply this.

5. Churchill Service Menu
Normal - 8 - Normal - 9 to access service menu from serial number 94003 onwards.
You may need to do this several times before it works.
For early models you must link 2 of 3 pins next to Eprom & press menu.

6. Churchill serial number label
Prefix NM means No Modulator
Prefix PD means PAL/D2MAC deemphasis selection on SCART pins.

The later "PD" Churchill will accept either D2Mac or PAL input
Read the label on the back which tells you:

"Disconnect pins 10 & 12 in lead for Mac based input. And short pin 10 to 12 in Scart connector for Pal based input."

What this means is that you should *always* cut the wires from pins 10 and 12 inside your Scart plug (label it "decoder end"). Leave the wires from these pins about 12mm long in case you need to connect 10 and 12 together. If your receiver can give MAC deemphasised output, select this in its menu (or however it is selected). If your receiver gives only PAL deemphasised baseband video output, connect pins 10 and 12 together inside the Scart plug at the decoder end of the cable.


You should always cut wires 10 and 12 in the Scart plug. Do NOT connect them to the receiver.

7. Where can I get my Churchill decoder repaired?
Highfield Electronics
445 Bolton Road
M27 2TN

Tel 0161 794 8441


I have 2 CHURCHILL Multimac D/D2Mac Multi card system,
both whistling. According to a belgian electrician ,
the transformers must be replaced.
Philippe Vandenbroucke

October 3, 1998

Hi, Philippe.

Your electrician is mistaken. All that you need to do is to replace three capacitors as follows:

C51 22uF/105°C/low ESR (causes high pitch whistling) replaces 10uF.
C34 l0uF/l05°C/low ESR (causes high pitch whistling)
C36 l0uF/l05°C/Low ESR (causes failure or "ticking" - won't start up)

I do not want to sell you a repair kit just for this :o)

Hi Repairman !

Let's hope this information will help some of your "readers".

For reception of D Mac transmission , I have been sent the following solution by Alfaglade:

"Modification for receivers with poor HF baseband output.
Remove Mac De-emphasis Circuit by clipping/lifting one end of R 90.
Eliminates locking/dropping out problems on D Mac transmissions."

They also sent me a fax to locate more easily the R90. This fax is not on my computer and as I don't have a separate fax , I can't send it to you now. I will try to scan and send it if you insist. But I think all resistors and capacitors are numbered on the pcb.

My decoder is connected with a scart to my Pace MSS 1001 IP , (decoder output Mac , Auto) and it works now perfectly since 30.10.95 , when I did the modification!!
Philippe Vandenbroucke


>I wrote to you a week or so ago regarding a problem I had with my
>Churchill D2mac decoder. The problem was the decoded picture had faint
>translucent black/white lines, they measured about 1 inch in height,
>crossed the full width of the screen and ran down the screen from top to
>I asked for assistance to which you replied that you didn't repair d2mac
>decoders, fair enough. Well in case you are asked this problem again I
>thought I would let you know of a fix I discovered via the WWW at
>Basically it recommends replacing C97 with a 100uf 40v Electrolytic. I
>duly went off to Maplins, the nearest match I could find was a 100uf 35v
>Electrolytic, the existing C97 was 100uf 15v, so I didn't think the 5v
>could hurt that much! Anyway, I replaced C97 and the lines have gone and
>I have a fully operational machine again.
>Thanks for you help anyway.
>Gavin Hall

Gavin, I'm very sorry. I actually *published* this solution in "What Satellite TV" magazine "Troubleshooter" section (Page 24 Dec 1998 edition) !!!

Frankly, I had forgotten because it was a solution given to me by somebody else a couple of months ago and not one that I had found myself when I *used* to repair these things.

I'm really grateful to you for setting me straight on this. Why your question didn't ring loud bells in my head, I simply don't know!

Thanks once again for taking the trouble to let me know and I'm extremely pleased that you solved your problem :o))

BTW the easiest way to fix this problem is to locate inductor "L6" just to the left of "U8".
Solder the 100uF "+" wire to the left end of "L6".
Solder the 100uF "-" wire to the wide 0-volt copper track just to the left of C47.
Leave the old C97 in place or, if lines still present on picture, solder another 100uF either to C97 wires or in place of C97.

Amazing little fan kit

With the Alfaglade Optimac, I mounted your fan on the card reader housing and
connected black to I.R. sensor housing; red to cathode of D2 ( the nearest of
the four 1N4007 diodes to the transformer- the cathode of D2 connected to
C56 negative). I didn't use a resistor as voltage was 9.5v.

Kind regards

Glenn Chamberlain.

>I have a Sky Analogue system comprising a Pace MSS1000 receiver and a
>Churchill Decoder, with two dishes connected. one to Astra 19.2 and one to
>Eutelsat Hotbird. Everything was working fine with this set up and I could
>receive D2Mac signals through the Churchill.
>Just before Xmas I had Sky Digital installed with a separate digidish, and
>had the Digital receiver connected through the MSS1000 (to the AV1 socket)
>so as to retain the Dolby surround sound.
>Ever since then I have been unable to receive any D2Mac signals and I don't
>know whether the Digital connection is over riding the D2Mac or what the
>cause is.
>I can receive a perfect picture in clear Pal on the Eutelsat satellite on
>all channels but as soon as a D2Mac signal is transmitted I get no signal
>although the screen appears to be trying to receive the signal ie I get a
>fuzzy scrambled clear screen as opposed to a fuzzy scrambled green screen
>with a D2Mac signal.
>I assumed the problem was dish related but I have had the dish alignment
>checked and it is receiving a really strong signal.
>Could you suggest any other cause, for example could it be the Churchill
>decoder that is at fault?
>I'm not convinced the Digital installation is the cause of the problem for
>if I disconnect the Digireceiver from the MSS1000, which in effect reverts
>back to the old setup, the problem is still there.
>Yours sincerely
> Mike Andrew

January 10, 2000

The last time someone reported this problem to us, it took a full SIX
months to determine the cause. What was it?

Well, he'd been given a gold-plated Scart-Scart lead TWO METRES in length
for Christmas. He'd used this to connect the Churchill and it had not
worked since. However, he omitted to tell us this. In fact he told us
that *nothing* had been changed and that the system simply stopped
He called out an installation engineer from the shop where he'd bought
the system FOUR times before the guy realised what the cause was. A 0.5
metre Scart lead cured the problem and the expensive 2 metre gold-plated
one was consigned to the waste basket. Needless to say, it cost him a fortune
for the call outs.

So, may I recommend you look at your Scart lead first? Use the one that
it always worked with. Some of these have to be connected a certain way
round for the later Churchills because pins 10 and 12 determine the PAL
or MAC input requirement and are specially wired at the Churchill end.

It's essential to determine whether your problem is caused by the Scart
lead, the decoder, the MSS1000 or the Digibox. Start by disconnecting the
Digibox entirely and replacing the original connections as they were.

If you can't get the decoder to work by yourself, all I can suggest is
that you take it to a specialist shop and pay them to test it.

>Dear Martin,
> Thank you for your prompt reply to my E.Mail
>yesterday, and more importantly thank you for solving the problem.
>It was as you suggested the scart lead that was the cause.
>My original Churchill scart lead always appeared a little flimsy and on
>occasions would come loose from its socket, so when there was a nice new one
>spare when I had Digital installed I made use of it - obviously wrongly. I
>did mention this to the installer when I was trying to solve the problem and
>he assured me that it would not be the cause - it just shows what he knows.
>Anyhow thank you once again.
>Kind Regards
>Mike Andrew

>Hello Martin,
>I have a churchill showing no outward signs of being alive, however having
>looked inside I know the fuse is intact and I have measured voltages on
>both sides of the transformer. So I think the beggar is pretentending to
>be dead.
>About 2 years ago i changed the three whistling capacitors and it had been
>working fine until recently.
>Prior to its demise it was showing 2 - 3 horizontal interference lines
>with one particular channel affected more than the others, I am thinking
>capacitors but as I am only a novice I thought I would ask "the" expert.
>Many thanks
> in Sweden
>who is grateful for previous advice and will soon be ordering various
>items from you.

I would personally change the small PSU electrolytics every year.
The 47uF/400v and the larger ones (1000uF or larger value) every 3 years.
Try replacing them first. It won't cost much to do that.

The CCU3000 microcontroller might have died if the 5 volt supply went too high (caused by PSU capacitors).

If you can't see any capacitor bulging then it's a good idea to actually measure the dc output voltages from the PSU, if you know how. If you don't know how then I recommend you take it to someone who does, rather than risk damaging it (or yourself). :o)

Kind Regards,


>Hello Martin,
>thank you for the advice.
>The culprit was the 25V 1000 microfarad capacitor.
>I swapped it for one from a faulty pace 500 and the churchill buzzed back to life.
>I will be ordering parts from you later on today hopefully.


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