Marconi 2305 Repair

[TheDefpom]

Hi Guys and Gals,
I thought I would just post a recent repair I did for a Marconi Modulation Meter, which I picked up from eBay as a faulty unit, I found a few issues with it, but I got it all fixed.

I put a video up on YouTube showing the issues I found, one of which was due to good old Tantalum capacitors failing.

[jkf1000]

Thanks for posting the video. I know when I purchased my 2305 quite a few months back there was very little information out there. Mine was advertised as sold as seen and untested but fortunately it is working perfectly so far, all I have had to do is new LEDs throughout, and remove and re-seat the lefthand LCD to clear a bit of oxidation on the contacts. Very useful bit of kit, just a bit on the large size. Karl

[TheDefpom]

I found a service manual online before I purchased it, so I had that to refer to also, although in reality it wasn't what allowed me to fix it, just looking around and testing/reseating things allowed me to narrow it down.

The manual was only helpful to test the power supply outputs.

I would if uploaded it here too, but the forum doesn't allow a 3MB file upload.

[tautech]

I found a service manual online before I purchased it, so I had that to refer to also, although in reality it wasn't what allowed me to fix it, just looking around and testing/reseating things allowed me to narrow it down.

The manual was only helpful to test the power supply outputs.

I would if uploaded it here too, but the forum doesn't allow a 3MB file upload.

You can post up a link to it Scott, those that find this thread in the future will be thankful.

[TheDefpom]

I find two manuals online:
The first seems complete, the second appears to be missing all the detailed drawings etc.

http://www.fracassi.net/iw2ntf/manuali/Marconi%20Instruments%202305.pdf
http://exodus.poly.edu/~kurt/manuals/manuals/Other/MARCONI%202035.pdf