Sky Digibox
Sky Analogue


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NOTE: This analogue receiver is obsolete. Most accessories and modifications mentioned on this page are no longer available.

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Amstrad SRD600

Amstrad SRD600 receiverDisplay shows PIN?
Disconnect mains power. Press reset switch with a match stick and hold.
Restore mains power. After 5 seconds, release switch. (Reset switch is accessible via a 3mm hole in the lower front panel, when the hinged cover is open). Also handy for various strange problems.

Blank screen on D2Mac channels:
Ensure that the Brightness, Contrast and Colour settings are fairly high for these channels. Use the Special Features button on the handset to select each of these features in turn. Increase them by pressing the "up" button and store by pressing the "Preset" button on the receiver.

D2MAC channels will not decode:
Replace IC1 (DMA2286) or the DMA2281. A special tool is required or, alternatively, use strong glue to fix a steel wire loop to the IC and pull!

Picture and sound may vanish if channel is changed:
(LNB voltage drops to 3 volts on changing from horizontal to vertical)
Replace C31 (2 2F/50v) in the power supply (rear, right) with a 10 F/16v.
(The LNB short-circuit detection circuit occasionally reacts too quickly).

Audio modes can't be changed:
Look for broken tracks on top of PCB around tuner.

Receiver dead:
A PSU repair kit is available from TELEPART but make sure the PSU really is dead (no voltages) before ordering the kit! If the power supply is OK, the problem is often caused by a faulty chip on the D2Mac decoder or a faulty CCU3000 or associated crystal.
To remove the square chips without damage to the sockets, buy our PLCC extractor tool!

Note: please contact TELEPART for a PSU repair kit as I no longer stock this kit.

Eprom Upgrade?
Several people have told me that a modified Eprom exists which will allow the receiver to tune higher for an Enhanced (9.75GHz) LNB. I have never seen one, although plenty of people have sent me Eprom copies. (Please do not bother!)

Secret Handset Codes
Press service button inside near the power supply and simultaneously press TV/SAT on the front panel. This puts the receiver in Service Mode. Don't use this unless you understand what you are doing! TV/SAT to exit

The Service Mode aids debug and allows various setups to be made. The mode is entered by pressing simultaneously the [Service Key] on the main board inside and the [TV/SAT] key.
You should first select a Mac channel and the mode will be displayed on screen.

The following list shows Service mode functions and their effect:

[Service]+[TV/SAT] Enters service mode. Displays software version if MAC.
[Search Up/Dn] VCO value (synchronisation time of Mac-adjust for match).
[Red][Reveal] Red Cutoff (RGB and RGB/PAL amplitude/black level).
[Green][Hold] Green Cutoff (RGB and RGB/PAL amplitude/black level).
[Blue][Update] Blue Cutoff (RGB and RGB/PAL amplitude/black level).
[8][Status] Red White drive (RGB and RGB/PAL amplitude/white level).
[9][Func.Sel] Green White drive (RGB and RGB/PAL amplitude/white level).
[Audio][Fn. Up] Blue White drive (RGB and RGB/PAL amplitude/white level).
[Yellow] Toggles between 1Vp-p and 2Vp-p MAC inputs.
[Select] Start displaying Black/White levels (AGC/clamp confidence).
[TV Programme Up/Dn] Displays NVM data (aids debug).
[Up] [Down] Changes NVM data at address selected by [TV Prog] keys.
[Sat Programme Up/Dn] Selects Card Reader modes for Vpp, Vcc setup and debug.
NOTE: Do not change these with a card inserted!
[Store] Stores changes during Service mode.
[TV/SAT] Stops Black white level display if enabled.
Otherwise exits Service mode.

Please note that the ex-factory settings have been very carefully chosen to produce the best picture. Also note that pressing RESET rewrites all information except VCO adjustment which should never change after having been adjusted during production. Service mode should be used only to check VCO, to set Vpp and to check RGB settings.

The [Service Key] can also be used to execute the special single commands by pressing certain keys with it:

[Polarisation] IM Bus Off. (Used to drive the Mac chips from a PC for
[Standby (IR)] IM Bus On.
[Text On/Off] Manually selects E7 de-emphasis.
[Full/Mix] Toggles AFT.

SRD600 as a decoder

Modify your Amstrad SRD600E to act as a D2MAC decoder.

Open up the Amstrad. Inside you will see that there are two PCBs on the right in piggy back configuration and a single PCB on the left. The PCBs on the right are the tuner, videocrypt and card interface. The PCB on the left is the D2MAC decoder. Locate the white PCB header in the middle of the three which connect the D2MAC card to the tuner card.

You will need to cut the second connection down from the top marked BB (for baseband) and to solder the centre core from a BNC plug to the left side of the connection. The outer shield of the BNC plug must be soldered to the pin at the top of the connector block (a GND rail) do not cut this pin.

The cable complete with the BNC plug can be fed through a small hole at the back of the case and the SRD600 reassembled.

Connect the BNC input to the decoder output of the other receiver and tune the Amstrad to any channel except 0 (0 - is the auxiliary and will blank out the picture).

The decoded output is now available at the right hand SCART socket on the Amstrad.

>Here is a mod for the Amstrad SRD600 so you can make it
>work with a ADX, automatically.
>Solder a 1K resistor on pin 19 of the IC 152 and a wire on
>the other end of the resistor and pull the wire out of the receiver.
>Now you have a 5 V pull up that you can connect to a ADX.
>Switch using HI/LO in the receiver !!
>Attached in this mail is also a epromfile I found that should give you
>extended tuning, (Srd6-2dl.arj) I have not checked it myself...
>Torkel Odeen

>When I want to tune in a frquency, I do as decribed in the users manual.
>But after I have saved the change, by pressing PRESET again, it keeps on
>counting down 5 or 6 numbers. Every time I checks the status it goes 5 or
>6 down. Eg. I press preset to change the Freq. change it to eg. 11473 and
>press preset once again to save it. But it counts another 5 or 6 Freq down
>to 11467.
>I hope you can help me.
>Henrik Therkildsen

The SRD600 uses automatic frequency control.

You can change the centre setting by adjusting the "OFF SET" potentiometer. This Pot is located beneath the top decoder board. You can get to it through a tiny hole in the plastic base moulding.

>My SRD600 is faulty.
>The receiver appeares normal until the picture goes into d2mac mode (when
>changing channel). In d2mac mode it is black with the on-screen channel
>marker just rolling around (out of sync.?)

Assuming that you have measured the Power Supply voltages and that they are OK, then the D2Mac board is faulty. You can try replacing crystals, the DMA I.C.s which are in sockets, the electrolytic capacitors ...

>The problem is fixed.
>It was as you suggested, the d2mac board. (I took a d2mac board from another
>receiver and tested).

>I assumed that the video signal was bad so I changed the electrolytic
>capacitor C372 and it worked at once. Now I have a steady picture from both
>Thank you for the help.
>Krister Muukka

This information is given in good faith, based on several years of workshop experience involving thousands of repairs. No responsibility will be accepted for any death, damage or injury caused either directly or indirectly by the use of this information. The reader should check the facts himself. It is assumed and stressed that the reader will be familiar with good, safe, electronic workshop practice and will be familiar with all tools, components and terms used. If there is any doubt about the reader's ability to carry out such work competently and safely, the work should be referred to a specialist engineer.

End of FAQ


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Version 1.2 updated on September 27, 2000
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