BT-SVS250 Matsui OP-10 FAQ page

If you find this information useful and want to thank me, why not buy one of my low-cost "virtual books" that you can download direct to your computer? My books can be read on-screen or printed out on paper. They are full of colour photos and illustrations. Click on "Books", above, for more information. Send this page address - CLICK HERE - to a friend !
NOTE: This analogue receiver is obsolete. Most accessories and modifications mentioned on this page are no longer available.

BT-SVS250 / Matsui OP-10

Return to SatCure index page

1. Why do the decoder messages disappear intermittently?

A kit of parts is available from SatCure - RELKIT17
Instructions are included. Please use the ORDER FORM.

2. After warm-up, my receiver shows "wavy lines and strange colour"
(herringbone interference).
This is caused by the 100uF (C460) next to the heatsink on the main board.
Solder a 220uF/25v/105'C capacitor to the legs of C460 or replace C460.
This part is included in the Reliability Upgrade kit RELKIT 17.

3. Where can I buy a remote control handset?
SatCure. Please use the ORDER FORM.

4. Where can I buy a Service Manual?
SatCure. Please use the ORDER FORM.

5. Can I get more than 129 channels?
Yes. SatCure supplies a 299 channel upgrade kit.

A complete fault-finding guide called "The Satellite Repair Manual edition 5" is available.

A cooling fan kit is available from SatCure. Please use the ORDER FORM.

6. My receiver is dead.
Check the fuse at the rear, behind the transformer. If it measures open-circuit, replace it with the SAME T500mA type. It melts to protect the receiver from mains power surges. If you fit a higher value fuse, the receiver will melt instead!

7. The manual says I can download from another identical receiver.

To download memory contents from one to another:

Connect fully wired Scart lead between receivers.
Leave both receivers in standby.
Point remote control at master unit. (Screen slave).
Press "download" with paper clip.
Master receiver displays three bars across the display.
Wait. It will display "End" when finished downloading.

8. My receiver makes a humming noise from the TV speaker

The noise may be intermittent or may occur only when the receiver has warmed up from cold. It is usually caused by failure of the two diodes (D405, D406) at the rear right corner of the lower Printed Circuit Board. The diodes are black with a silver or white stripe (indicates cathode end). Replace these diodes with higher rated BYV95A type. Please use the ORDER FORM.

If the picture is also affected, then there may be a different fault such as a faulty 6 volt regulator.

9. How do I dismantle my receiver?

Use a Pozidriv screwdriver to remove 2 screws at each side and 3 at the rear.
Use a thin blade to bend out the rear side corners of the cover then hinge it forward from the rear.
It will click out with a bang but this will not do any damage.

Remove all the screws from the rear panel. Take careful note of which screw fits in which hole. The RF modulator screw has no point.

Remove the two large screws which secure the transformer and the adjacent small screw that holds the fuse board to its pillar. Lift these items out and place them behind the receiver.

Remove the two screws which hold the top black heat sink plate to the vertical heat sink and place the top heat sink behind the unit.

Remove the two rear screws and the two front self-tapping screws which secure the decoder board. If there is red varnish *inside* the screw head, remove this with a soldering iron first. It is MOST important that the screwdriver fits the screw head. You must NOT exert downward pressure on the rear screws or you will crack the bottom board which is unsupported. Lift out the decoder board and place it behind the receiver. You can unplug the two connectors if necessary.

Remove the 6 screws which secure the bottom board - one is in the heat sink bracket. You can now lift out the main board.

10. Adjusting RF audio for Europe

> My SVS260 is (obviously) a British Receiver and as such there is a
> minor incompatibility with the German TV system. As you are probably
> aware, in Germany the audio carrier is offset from the vision
> carrier by 5.5MHz as opposed to 6MHz in the UK. While this does not
> affect the SCART output, it would be advantgeous to have the
> standard UHF connection working as well.
>
> This necessitates a change to the RF Modulator, but I have had
> little success in locating one. Ideally, I would like to locate a
> type I/G switchable modulator, but would settle for a G type. Do you
> have any idea where I might be able to get hold of one?
>
> Thank you in advance for your attention. I hope that I have not
> wasted too much of your valuable time.
>
> Yours Sincerely
>
> Robert in Wiesbaden, Germany...

There is an adjuster in the RF modulator for this. However it's a tiny black fragile ferrite dust screw core. You can access it without completely dismantling, as follows:

Look at the rear. If it's the same as the scrap one I have here, the RF modulator will have a turquoise plastic adjuster slot for setting the UHF output channel.

From the exact centre of the turquoise adjuster, measure 18mm vertically downwards towards the test switch and make a mark. From this mark measure 5mm to the right and make a mark. This is the exact location to drill a hole - or melt one with a soldering iron.

Make the hole at least 6mm diameter for ease of access. The adjuster is recessed about 8mm deep inside the RF modulator - about 10mm with the thickness of the plastic rear cover. You need a jeweller's screwdriver with a flat blade of 1mm.

With everything connected, try unscrewing the adjuster by a turn or two. Do it gently or it WILL break

> Dear Martin,
>
> Apologies for not getting back to you sooner, pressure of work and
> so on has meant that until this weekend, I have not got around to
> making the adjustments to my decoder. Finally, 1 have managed to
> find the time and 1 am very happy to say that your advice was
> perfect. Everything is working marvellously.
>
> Thanks very much for your prompt and helpful service.
>
>Robert Ramsay

11. I get no audio from RF or from Scart connection to the TV

FM demodulation is performed by U301 (beneath the board) and the associated circuit.

It is common for U304 (78l05 regulator) to fail. Measure its output voltage which should be 5.0 volts. If the voltage is less than 5 volts, replace this regulator.

HOW DO I PLACE AN ORDER?

DISCLAIMER
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.

Copyright ©1998 SatCure
Version 1.5 updated on September 12, 2000
This file may be downloaded for private and personal use but NO part of it may be published in any form without the prior permission of the author.
Return to SatCure index page
Send this page address - CLICK HERE - to a friend !