Rohde & Schwarz Universal Radio Communication Tester CMU200: PSU problem

[richnormand]

About using a CF card. It will work, as this is what I have setup, with the adaptor previously mentioned. That is what I meant about using a flashcard instead of the original HD.

If you do that make sure you use the card type that is bootable (not all of them are. The bootable ones tend to be also more expensive I found out). There is a thread somewhere on this forum about that. I'll post the link when I find it.
The other thing to be aware of is the CF cards do wear out over time with this type of usage, so make sure you have a good bit copy of the original disk.

Before considering the switch to LED for the display I would try just changing the inverter fuse (cheap and easy) and look at the state of the fluos before. If they are still good you might still get a long service time out of them.

It will be interesting to find out what is the reason the PSU signal does not work from the front panel.

have fun!

[richnormand]

"There is a thread somewhere on this forum about that. I'll post the link when I find it."
Well the thread was about making a bit copy of the HDD but I relocated where I found the CF flash information from my notes.

https://lowendmac.com/2015/the-lowdown-on-using-compactflash-to-replace-an-ide-hard-drive/

Note the "You should be sure you’re using a UDMA CF card, as non-UDMA cards are not generally bootable when used with an IDE adapter." in the article.
This is exactly what I found the hard way and after getting a UMDA card from eBay it all worked perfectly. Keep in mind that CF cards will deteriorate with the number of read/write but mine has been working for a couple of years. I burned a backup copy on CD and also kept the original HDD (belt and suspenders) in my CMU200 three-ring binder.
Booting the OS is a tad faster but most of the time is taken initialising all the modules.

Also with the adapter double check the ribbon cable polarity as my cable allowed plugging it in two different positions.

[wiredwrx]

"There is a thread somewhere on this forum about that. I'll post the link when I find it."
Well the thread was about making a bit copy of the HDD but I relocated where I found the CF flash information from my notes.

https://lowendmac.com/2015/the-lowdown-on-using-compactflash-to-replace-an-ide-hard-drive/

Note the "You should be sure you’re using a UDMA CF card, as non-UDMA cards are not generally bootable when used with an IDE adapter." in the article.
This is exactly what I found the hard way and after getting a UMDA card from eBay it all worked perfectly. Keep in mind that CF cards will deteriorate with the number of read/write but mine has been working for a couple of years. I burned a backup copy on CD and also kept the original HDD (belt and suspenders) in my CMU200 three-ring binder.
Booting the OS is a tad faster but most of the time is taken initialising all the modules.

Also with the adapter double check the ribbon cable polarity as my cable allowed plugging it in two different positions.

Thanks for the info once again.  I will keep that all in mind.  First, need to get the unit working, then I can get to improving it.

[Rollin Hand]

i try the cf with one Chinese adapter didn't work ,did not boot.

[wiredwrx]

An update, which I hope will be helpful to others.

Sourced a replacement membrane, and now she works as she should.  Also replaced the SMD fuse on the inverter board, and it works also.  I was able to de-solder the old fuse, and solder in a replacement (I used https://tinyurl.com/ycdcxm9p) with a regular iron with a pointed tip and a tweezer.  It really wasn't too hard, and if I can do, likely anyone can do it.  Only thing is, It is dimmer than the other CMU200 I have, so I think the reflector has curled around the tube as has been suggested elsewhere, or perhaps the glass is discoloring along with the curled tube.  Gonna consider using LEDs.

Now, for the ask

I know I have several options and cards that I don't need.  Anyone know of a list, and perhaps a how to/diy on what can be removed, and how?  I know I have B83, because when the unit boots, I get a message about initializing B83, which lengthens the bootup significantly.  So, I wouldn't mind paring down the un-eeded/un-useful options and cards.

Thanks for all the suggestions and help,
Michael

[ZL1CVD]

Picture shows bare minimum hardware for basic RF (spec analyser, RF generator, RF power meters).

[wiredwrx]

Thanks for that.  Do you know if the OS/Software will throw a fit if I remove the modules?  Also, if you are able, do you mind taking pics of the coax between the modules, because I think I will need to move many connections if I remove the modules.

Thanks again,
Michael

[ZL1CVD]

Sorry, that is the only picture I have of bare minimum. I sold that over year ago now. You can look closely to work it out. There are service manuals around and top plate show interconnections.

When you remove module/s, you must blank of the air duct so other modules get correct cooling. I use aluminium roofing tape because I have it and it has EMI shielding properties. But you can use other tape you have.

Once you finished removing everything, start up version manager and rung 'firmware update after module change' - this is from memory, it may be slightly different wording but means same. This procedure takes some time - maybe 15 minutes or more. It updates everything to make sure all path attenuation's and firmware is correct for what is left installed.

If you need more information, look at the service manuals that are around. There is allot of information in those.

[ZL1CVD]

Here is another internal bare minimum picture..

[Ice-Tea]

Thanks for that.  Do you know if the OS/Software will throw a fit if I remove the modules?  Also, if you are able, do you mind taking pics of the coax between the modules, because I think I will need to move many connections if I remove the modules.

Thanks again,
Michael

The wiring diagram is printed on the cover of the modules.