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themadprofessor
18-09-2005, 16:39
Hi,

I have only just become acquainted with DRM Radio. I got interested as a side effect of getting some DAB radios because a DAB portable was the only radio to work in hospital.

Anyway -

I am trying to experiment with DRM reception on the cheap and after trying to use two different amateur radio transceivers without any success because I think the filters are too narrow I have purchased the Eelektor board with a 12KHz output.

Where is the best place to get all the components for this board? Obviously the Rs/Cs are all easy to get however it seems that one or two of the ICs are not very easy to get. The german sites which are referenced from the Elektor website only seem to offer complete modules and I do not want to pay their prices.

I would be grateful for any tips, both on where to get the components, and also on DRM reception in general.

I am located near Peterborough and can pick up 5990, 6095 and 7320. However all the Medium wave frequencies are either completely inaudible or blocked by other signals. 1440 seems to be occupied by Radio China every evening!!

Rgds

Chris

dk8cb
19-09-2005, 09:40
Originally posted by themadprofessor
1440 seems to be occupied by Radio China every evening!!

This is because BCE (Broadcasting Centre Europe) is renting its transmitter (the same one that is used for RTL's DRM transmissions) to China Radio for a few hours each night. If you tune in to 1440 kHz after 23:00 UTC, there will be a DRM transmission from the same transmitter.

Roland

themadprofessor
19-09-2005, 09:50
Originally posted by dk8cb


This is because BCE (Broadcasting Centre Europe) is renting its transmitter (the same one that is used for RTL's DRM transmissions) to China Radio for a few hours each night. If you tune in to 1440 kHz after 23:00 UTC, there will be a DRM transmission from the same transmitter.

Roland

Thank you for that info. I think that I tried last Sunday after 2300 UK, but still didn't receive any DRM, however I shall try again this evening.

I notice that there were some guys on this forum using HAM gear to receive DRM, however would I be right in assuming that they are all using 455/12 KHz converters which I assume bypasses the internal SSB narrow band filters of the HAM gear.

Also Can you suggest a source of supply for the the difficult to obtain parts of the Elektor kit. I don't want to buy a complete module just the components. Do you know of any member of this forum that has constructed one of these modules and who might offer me some handy tips on construction and alignment (not that there is much).

Thanks for your help

Chris

dk8cb
19-09-2005, 10:15
Originally posted by themadprofessor
think that I tried last Sunday after 2300 UK, but still didn't receive any DRM, however I shall try again this evening.

23:00 UTC = midnight UK time in summer!

Roland

df8uo
19-09-2005, 17:15
Originally posted by themadprofessor
Hi,

I am trying to experiment with DRM reception on the cheap and after trying to use two different amateur radio transceivers without any success because I think the filters are too narrow I have purchased the Eelektor board with a 12KHz output.


Hi Chris,
normally it should not be any problem to modify amateur radio equipment. My experience (inbetween i modified two transceivers) is positiv. In most cases you can get the 455/465 kHz signal before or after the AM filter. What type of amateur transceivers did you try to modify?
Regards, Daniel

themadprofessor
19-09-2005, 17:27
I have not tried to modify one yet as I am only just getting into the reception of DRM.

I have a Trio TS 430 which is my main transmitting rig so I am reluctant to hack it around!


I also have a SGC SG-2020 QRP rig that looks as if it would be even more difficult.

So that is why I purchased the Elektor board and have this afternoon printed the parts list and am going to try and get suppliers for them.

I have emailed "Geist Electronic-Versand GmbH" and asked whether they can supply sets of components and what the cost would be.

I wonder what the performance would be with the Elektor board? I was just reading the instructions and the author implied that it works quite acceptably.

I guess it would not quite equal the performance of Amateur rig, but as I said before I am reluctant to hack my main rig around!!

Thanks

Chris.

DRM-Fan
19-09-2005, 23:07
HI Chris

There is a place in Holland where you can obtain all the parts, not sure all components are available in the UK for the Elecktor.

Perhaps someone can give the url of the Dutch supplier, can't quiite remember

It is a good design though maybe a bit deaf. In a few months there will be stand alone DRM radios available to buy though