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Dear Members,

I just finished wiring up my receiver modules and taking care of this and that? when you first light of any home brew project.? Us Amateurs on this side of the earth have the US National Bureau of Standards Radio stations on 2.5MHz, 5MHz, 10MHz, and 20MHz blasting out time and information signals 24/7.?? When I lit off my DAYLIGHT ANALOG radio and was tuning around I had a beat note in my receive audio.? Sure enough the 5MHz WWV time signals were sneaking through my 7MHz Band Pass filter, through the first mixer, crystal filter and beating against the BFO oscillators signal in the 2nd Mixer.?? The Cure is simple.? A 5MHz trap made from a T50-2 core with 32turns of #26 wire and put in series with a 250pf of capacitance. (I used an old compression trimmer from my junk box but the needed capacitance is somewhere between 220pf and 250pf to suck the 5MHz signal out.?? Now my DAYLIGHT ANALOG receiver can listen to 40M SSB DX from Central and South America, FT8 tones, and some really good clear CW.?? The only think to note is that Experimental Methods in RF Design on page 5-12 recommends that the PTO and the BFO signals be about 5V Pk to PK.? My PTO was much lower than that and I have changed the 78L05 voltage regulator to a 78L09 and my PTO signal is not quite 5V PK to PK but the received signals have improved.? So, I believe that is worthwhile doing.

For those who are curious what the 5MHz trap looks like in reality, Here is a picture of mine.? (It is not the gold standard, but it did work very well)

Keep at it.?? This radio is well worth the effort to collect all the parts and build it.?? It will teach you many things and not just the stuff that comes out of a book (but the book helps....hi hi)

Take care and have fun.?

73 Dave WA5DJJ
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73 Dave WA5DJJ
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EMAIL: dhassall@...