Saturday, February 25, 2012

I am 902 Mhz Playing Again

It has been a bit since I last posted, I am baby sitting some Painters and Sheet Rockers as they continue to remodel the office areas of my work place.


Yes that is Paint Fog , the flash caught it in the air.


Sheet rockers have been here! - This will be our product display area.

So I thought I would do a bit of 902 Mhz playing as well.



Today I am testing the rx VCO lock range of a stock Kenwood TK-981 that has had the front end filters changed out to a set centered in the 902-928 Mhz ISM band where we as HAMs have a allocation to transmit & receive at for our scientific, educational & hobby use.


These filters are used to keep unwanted out-of-band RF junk out of our radios and to make them more sensitve to the desired part of the band ie 902-928 Mhz, originally they were center on the 936 mhz part of the commercial part of the LMR band, 929-960 Mhz areas.



As you can see removing and replacing these filters is no EZ task.
It is all surface mount components, all which take time and patience to do and of course the right tools.


This particular radio's VCO got flakey about 924.2625 Mhz , so I need to adjust the VCO voltages and see if I can bring it down in frequency some more. The goal is to get full band coverage 902-928 Mhz on the receiver.
  
All for Now
Comments Are Always Invited

Sm0ke