[NLRS] 6GHz microwave stuff

[Doug Reed]

I'll be helping some friends scrap out an old microwave relay site over 
the next few weeks or month. It has a lot of waveguide based equipment 
that I'll be taking and scrapping out for parts. It is all marked as 
being in the 5.9-6.4GHz band. The waveguide filters cover twelve 40MHz 
channels within the band. What I can see includes a lot of microwave 
brick oscillators and waveguide components of all sorts.

Does anyone want to try building a rig or a beacon from these parts? A 
6.2GHz brick LO with a 440MHz driver might work.... Any one of the 
bricks with a SI570 oscillator and rigged for QRSS or PSK31 or JT65 
might work better. Or FM modulate the brick itself?

Most of it is Northern Telcom model RD-6C digital microwave receivers 
and transmitters. There is also some older generation, Rockwell- Collins 
MW-109E-1. Both models are solid state up through the power amps. The 
equipment all runs on -24 volts DC or on lower internally regulated 
voltages.

The NT is listed as .5, 1, or 2 watts output, depending on model. The 
Collins was originally either 5 or 10 watt TWTs but they have been 
replaced with solid state amps and I don't know their power out. If 
anyone knows if the amps will cover the 5.6GHz band, let me know. Since 
they are spec'ed down to 5.9-6.4GHz, they may work down to 5.6GHz.... 
I've got manuals for most of the pieces too.

NT brick is NT1H98xx DRO phase-locked oscillator +16dBm output
NT RF pwr amp is NT1H63BA or B or C

There is a lot of WR137 waveguide coming out too. The waveguide will be 
sold for copper scrap value. If there is any specific fitting, bend, 
piece, or length of waveguide that you might need for some project, let 
me know and maybe I can save it for you. There are many pieces over 3' 
long so if you want to make a slot antenna, now is your chance to get 
the materials.

One other thing you can make with old waveguide is interdigital filters. 
Several years ago I made a nice filter for 1240-1300MHz based on a 
section of WR229 and the design charts from the ARRL Microwave Handbook. 
I used brass hobby tubing and drilled matching holes in the tubing, 
measured and cut the brass elements a bit long, then marked the correct 
length and slide it into the holes. I did use a sweeper for final 
alignment but it was pretty close based only on measurements. Yes, pipe 
cap filters are a lot smaller and easier to tune, but will not be as 
durable or handle as much power as the waveguide version. :-)

I'll know more by Wednesday and will probably have some parts removed to 
look at by then. If you've got a suggestion for anything I should be 
looking for, let me know.

We'll also be removing the old open frame relay racks. They will go to 
scrap unless someone asks for one. These are telco standard, a base 
about 18" deep x 19" wide with vertical 6" channel uprights about 7' 
high. All drilled and threaded for 19" relay panels. They will support a 
ton of weight although you will need to bolt the base to the floor or 
the tops to a rafter if you don't want it to fall over.... :-)

73, Doug Reed, N0NAS.