RadioBanter - View Single Post - 88-108MHZ BC RX 'pulled' for 137MHz Wx signals?

triode · 12:49 AM

Quote:

Originally Posted by Fred McKenzie

In article ,
lenseman wrote:

Has anyone pulled a VHF Rx to enable the Wx APT transmissions at
137.1MHz? If so, how easy is the conversion?

If not, a downconverter to enable the Wx signals to be received on a
VHF wideband broadcast receiver.

David-

If the FM receiver has high-side injection for the broadcast band, you
may be able to pull the local oscillator a bit higher, and receive the
137 MHz signal using low-side injection. I think the receiver's RF
amplifier stages would need to be retuned as well. A counter would be
helpful to be sure you are receiving the right signal.

I think it would be easier to build a crystal controlled converter to
translate the 137 MHz signal to the FM receiver's IF frequency.

Fred

What would be the point.... the FM radio already can convert the 137megs to 10.7 megs with just modified coils! Why complicate something simple? A signal generator would be more useful than a freq counter to get it on frequency. The beauty of it is it will also receive aircraft .... the FM discriminator on cheap FM radios will also happily demodulate AM. I have done this, it works well, and takes just 30 minutes.