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The M/ACom "white box" transverter was used as the basis for this project.  With 100mW out, and power monitors and extensive filtering, this is a step up from the previous project.   This has common RF output so I mounted 2 Dow-Key TTL controlled relays on the back of the dish, and also installed a 22db gain TRW surplus amplifier module.  The Tx side of the relays goes straight through for 100mW output, but I plan to later add a 1W or 2W amp. 

The placement of the amps on the back of the dish will allow be to consider using a flexible cable for tripod mounting the dish, with the rest of the unit mounted suspended blow the tripod to lower it tendency to tip over in the wind on a hill top.  for now I have everything on a piece of 3/4" oak veneer plywood, so that when it does blow over, it will look nice doing it.

Antenna: The dish feed tuning was accomplished using 3 screws in front of the probe (brass 4-40) and one brass 4-40 screw just above/opposite the screw.   This was good for 22dB return loss.   I picked up some surplus 8-12GHz directional couplers which allowed me to tune the feed.   The probe is a long gold plated SMA connector  soldered to the copper pipe.   The dish was milled out slightly to slip in the pipe.  A brass disc was soldered to the pipe and used with copper tape to fasten it permanently in position and to seal any possible leakage.  The dish uses a circular waveguide through the parabolic dish with a clear plastic spacer at the end mounting a small reflector disc.

I am using surplus isolators in the TX and RX paths at the T/R relay nearest the dish feed.

The blue device is an dual directional coupler.  I leave it in full time. I use it for 2 purposes:
a. Power forward and reflected measurement for dish tuning
b. Insert a 10GHz weak signal source.   The coupler adds 20dB attenuation to my weak signal source and results in a S4 signal about 12KHz below 10,368.1MHz calling frequency.  I tune down from my 145.100MHz IF frequency  of FT-817 and find the signal, then I can tune up 12KHz and be reasonably sure what frequency I am on.

The above photos show the overall interior arrangement of the surplus case used to house 10GHz transverter.  The PLO brick at 10,223.0MHz requires -20V, and the White Box requires +12VDC and -5VDC.  You must ensure that +12 is not present before the  -5VDC or damage may occur.   To protect the transverter, to sequence and control the T/R relays, and to monitor the output power with a 1ma analog meter and a peak LED I designed a PCB in 2 sections below.

PLO:  A 10.223GHz California Microwave PLO brick is the LO.  It uses a 94.67401MHz TO-5 crystal.  This unit has a crystal oven so it drifts around only a bit at startup.

Visible in the back right inside corner is the DB9 connector that runs to the dish for power and relay control. Also I mounted a pair of power poles on a small PCB on standoffs.  This is the 12VDC power input and also provides a convenient place to power the IF rig.  A 3rd plug would have been nice to power the weak signal source (aka calibrator).  My weak signal source uses a 15.36MHz TCXO that is very stable as it turns out.  It provides harmonics near the calling frequency of the upper microwave bands. 

The right side is the TX monitor.  It is a pulse stretcher and when it sees a strong enough TXMON signal it ensures the LED stays on long enough to see it.  The threshold is adjustable.  There is another pot at the input to calibrate the 1ma analog meter for full power reading.  I use a -40dB step attenuator in the IF drive to control power output.  There are fixed attenuators i the TX and RX IF paths that serve to insert minimum attenuation from the FT-817 regardless of the step attenuator setting and to prevent overdriving the IF RX.

The left side of the PCB is the transverter control.  It uses a -5VDC relay to enable the  +12V supply to protect the transverter.  A versatile connection scheme to the external T/R relays allows relays with indicator contacts to be used as interlocks in the PTT sequence this ensuring it is not possible to TX without the relays being in the right position.   I am using some surplus K&L relays with indicators and operate on 12VDC, always a lucky find.  To use relays without indicators, just short the header pins for the interlock circuit.  There is a sequencer built into the board that should do fine with normal relays.

Since the FT-817 is a common IF configuration, I added another BNC coaxial relay that you can see at the rear of the interior, mounted on a vertical bracket with attenuators attached.

The above pictures are the back side of the front panel.  I flush mounted the 1mA power monitor meter and used LEDs for TX power indication and power on status.  The whole unit operates on 12VDC.

The unit needs -20VDC for the PLO brick, -5VDC for the white box RX, +5VDC for logic and TTL relay control, and +12 for the white box TX and RX sections.   I used surplus DC-DC converters 12V input with isolated 5VDC output at 300mA.  I put 5 units in series to create +5, -5, -10, -15, and -20VDC at 300Ma max total chain current draw.  300 was just enough to do the job.  See the schematic for wiring details.  To mount the modules I used scrap single sided phenolic board and used a Dremel tool to grind out the "bus bars".  Then I drilled holes for wire termination and filter capacitors.  Very simple and cheap.  The boards were mounted to standoffs on the chassis side rails.

Schematics and PCB files.  You can download the zip file that contains the ExpressPCB schematics and PCB layout files.  You can send the PCB files directly to ExpressPCB to max a number of boards.  The zip contains my Rev 1 modifications to fix up a couple mistakes in the first board set.  There should be no errors in this version I know of. 

Using the TX Monitor.  The monitor circuit is separate from the rest of the board.  You can cut the board apart if you only need one piece or the other.   I jumper 5V over the 2 parts, and connect the white box TXMon cable to the board input and adjust the meter and threshold pots.  This circuit is borrowed from W1GHZ and can be found on one of his Sequencer PCB designs.

The control section is very generic and can be adapted to most any collection of surplus transverter parts.   My idea with using the larger modular layout was to be able to swap out 10GHz parts for 24GHZ for later experimentation.   The unit works so well that I will likely not disassemble it though.   I can do a 90mile shot with S8 signals and both ends 15-90mW each.   The small dish is not very critical and is relatively easy to find signals.  The preamp on the back of the dish helps a lot also.  It is a surplus TRW module, nothing terribly spectacular, but the whole unit is a solid performer.

The above 2 schematics are the same control boards but one version has the DC supply using the 5VDC DC-DC Converters, and the other shows the external T/R relay wiring for the RX preamp and future TX power amp.  These extra circuits are not on the PCB, but are included for completeness.  As a result when opening the PCB layout file, it will warn of netlist errors.  You can ignore these errors or delete the extra sections and put them in their own schematic file.

10GHz Control Module Schematics and PCB Files

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