RX-7200 | FM band coverage Expansion How-To

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Superduper

Member (SA)
There was a discussion on the russian boombox enthusiasts forum shizaudio regarding expanding the FM band coverage of the National RX-7200. A member of that board (Vlad33) posted and shared his mod, unfortunately it was in Russian. Fortunately Boomboxery member Alex (Mystic Traveler) is also a member there, and has donated his time (in collaboration with Vladimir) to collect, summarize and translate that process so that that knowledge is available to English speaking crowd too.

I have included the how-to into our WikiBoombox archive. For those that are interested, you may view the article, as well as the RX-7200 wiki there.

How to Article:==> http://www.wikiboombox.com/tiki-read_article.php?articleId=3

Wiki Page of RX-7200 ==> http://www.wikiboombox.com/tiki-index.php?page=National+RX-7200
 

BoomboxLover48

Member (SA)
Dec 3, 2010
5,750
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Chicago, IL
The work shown here is for top ranking professionals like Superduper. :yes:

For untrained hands, is very easy to ruin the radio section of one of the most complicated boomboxes ever made!
RX7200 is fully packed and not at all an easy box to work on.
It was a jaw dropping experience for me to see the interior parts of RX7200. :jawdrop:
I am glad I have a fully working mint one!

I won't even attempt to fool around with mine. :no:
I will use FM radio input from my IPad or phone to play FM. :yes: :-D

I've added a few pics of the interior parts of my RX7200.
 

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toshik

Member (SA)
Mar 1, 2015
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St. Augustine, FL
BoomboxLover48 said:
The work shown here is for top ranking professionals like Superduper. :yes:

For untrained hands, is very easy to ruin the radio section of one of the most complicated boomboxes ever made!
RX7200 is fully packed and not at all an easy box to work on.
So I do not qualify for being one (professional) anymore ? :-)
Superduper was the one who sent his 7200 to me for modification when I came up with it 2 years ago, not vice versa :-)
https://boomboxery.com/forum/index.php/topic/23298-my-national-rx-7200-88-108-mhz-fm-and-120vac-modificationsrepairs/
 

BoomboxLover48

Member (SA)
Dec 3, 2010
5,750
270
83
Chicago, IL
toshik said:
The work shown here is for top ranking professionals like Superduper. :yes:

For untrained hands, is very easy to ruin the radio section of one of the most complicated boomboxes ever made!
RX7200 is fully packed and not at all an easy box to work on.
So I do not qualify for being one (professional) anymore ? :-)
Superduper was the one who sent his 7200 to me for modification when I came up with it 2 years ago, not vice versa :-)
https://boomboxery.com/forum/index.php/topic/23298-my-national-rx-7200-88-108-mhz-fm-and-120vac-modificationsrepairs/
Oh my! I didn't say that. :lol: :lol: You are the first person to tell me about this modification more than 2 years ago. I was so hesitant to ship it it. :-D

You are not just qualified, but over qualified. :-D

I know you are very good at RX7200 and all. :yes:
 

Superduper

Member (SA)
As I have said and posted feedback here before, Toshik has done this mod successfully.

This modification is not for the casual boombox hobbyist. I said in the other forum that you need to read through the modification steps thoroughly beforehand and if at any point you feel lost, STOP and don't attempt this modification. Resetting the controller to support 88-108 mode and activating the extra digit is the easy part and I feel comfortable that most folks here can do that without too much difficulty and it can be undone. However, retuning the tuner board to expand the band coverage will take some skill and according to the instructions, requires you to unspool and trim a couple of coils. These can't be easily undone. If you don't understand what is happening in the step/step description, I don't recommend you attempt it. Also, Vlad gives instructions for tuning using just over-the-air broadcast stations as reference. I suggest you use a signal generator to do this instead. That way, you can feed the appropriate low and high end RF signals for reference instead of an over-the-air broadcast.

Again, if you feel like it might be too technical for you, then it probably is. Send your unit to Toshik or Caution or some other tech.
 
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