Just finished a third one for my son to use with his Ekco A22. As with the first two it was built on a PCB as covered in this thread and it works fine. I built it along similar lines to the second one and again, as I couldn't find a suitably sized ABS box, I made a little comb-jointed wooden one. Not really much more that I can add, but I've attached a few pics.
The first pic shows 6BA brass pillars soldered to the underside of the front panel, which was scrap double sided FR4 PCB laminate.
The second pic is the completed PCB, with the FM module soldered upside down on Veropins on the underside of the PCB. (where the push button switch is also mounted).
Third pic is the completed PCB ready to be fixed in the box.
Fourth pic shows the front panel with an ink-jet water-slide transfer label ('decal) fitted.
Fifth pic is a close-up of the PCB fitted to the stand-off pillars, correctly spaced from the front panel for the push button.
Looking back over the thread, for anyone not having PCB facilities, it's clear that a number of constructors (not forgetting Guy Fernando - the designer), have successfully built this most useful little project on strip-board. The trickiest part by far is mounting the little FM module, but as John ('60 old john') at post 15 showed, and other have since, it can be done with care. If the module is trashed, it's not the end of the world - they can be found on ebay from UK suppliers for around £2.00 each.
As to my own input to the thread, perhaps posts 40 45, 49, and 57 are the most relevant. For anyone with a laser printer but without a UV light box, the 'laser print/iron on' technique seems to be widely used with success - there's lots of videos on youtube which show how it's done. Just make sure that the image is reversed for ironing one or the PCB will come out back to front! For those who do have A UV light box, I can commend the use of the negative dry film technique (which requires a negative PCB mask). I'd reiterate that due to time constraints, I'm not able to make PCBs for others.
Guy Fernando - the designer, (forum member '14iy'), wrote a very informative post #54 which answered several queries. Guy's website, where the full original BVWS article can be found and programmed PICS can be bought for £12.95 inc Post is at this link:
http://www.i4cy.com/m0oox/fm2am/FM%2...0Converter.pdf
I hope this update might encourage a few other forum members to have a go at building one.
For anyone wishing to build a simple 'pantry transmitter' which enables any input (MP3 player, audio output from an FM or DAB radio etc) to be re-transmitted onto M.W. I can highly recommend the 'Mini-Mod', which is covered extensively in other threads.