10 GHz - new life for an old dog (xverter)
Posted: Wed Nov 30, 2011 9:12 pm
New life for an old 10 GHz transverter - the MaCom 3 cm "white box" moves to reference locking with the XDK PLL.
In previous Field Day & other microwave activity sessions, my MaCom WhiteBox based 10 GHz transverter has been somewhat of a pain to use, with strange wanderings of the LO signal, even between Tx & Rx. It was often the case that I had to keep fiddling the IF frequency to finish a contact.
Following on from much thinking on my part, and some discussions with Ralph VK3WRE, I finally took the plunge last week.
I took a VK3XDK PLL board, removed the SMA connectors and tacked on a slightly cut down MiniKits GALI-84 KIT board to the PLL board output, after adding the ERA-2 to the PLL board.
Next step was to remove the oscillator board from the MaCom brick oscillator. Use this to measure up for a small Al sheet, mark & drill hole positions for the brick oscillator mounting holes. Position the XDK PLL/GALI-84 combo, mark out, drill & tap mounting holes for M3 screws to mount the combo onto the Al sheet. Solder on a length of RG316 coax to the output of the GALI-84 board to feed through into the chamber on the other side of the brick. Also prepare a suitable cable connector combination to bring the 10 MHz reference signal into the the Ref port on the PLL board.
The PLL out signal from the GALI-84 board was soldered onto the track between the circulator and the SRD multiplier on the other side of the brick. Added a biggish snowflake to the track close to the existing trimmer cap and checked on the Spec An. Jackpot - +10 dBm out at 10224 MHz. Now simply reconnect everything back up and we had a frequency stable signal on 10 GHz, apart from the variations in the FT-817 IF.
Many thanks to Ralph for his assistance & encouragement.
So any others out there with a WhiteBox system might consider a similar approach. I know that there should be at least 16 in this country, as I imported that many & distributed them to interested amateurs at my cost price.
If I find the time, I might organise some photos to add to this brief description.
Peter VK3PF
In previous Field Day & other microwave activity sessions, my MaCom WhiteBox based 10 GHz transverter has been somewhat of a pain to use, with strange wanderings of the LO signal, even between Tx & Rx. It was often the case that I had to keep fiddling the IF frequency to finish a contact.
Following on from much thinking on my part, and some discussions with Ralph VK3WRE, I finally took the plunge last week.
I took a VK3XDK PLL board, removed the SMA connectors and tacked on a slightly cut down MiniKits GALI-84 KIT board to the PLL board output, after adding the ERA-2 to the PLL board.
Next step was to remove the oscillator board from the MaCom brick oscillator. Use this to measure up for a small Al sheet, mark & drill hole positions for the brick oscillator mounting holes. Position the XDK PLL/GALI-84 combo, mark out, drill & tap mounting holes for M3 screws to mount the combo onto the Al sheet. Solder on a length of RG316 coax to the output of the GALI-84 board to feed through into the chamber on the other side of the brick. Also prepare a suitable cable connector combination to bring the 10 MHz reference signal into the the Ref port on the PLL board.
The PLL out signal from the GALI-84 board was soldered onto the track between the circulator and the SRD multiplier on the other side of the brick. Added a biggish snowflake to the track close to the existing trimmer cap and checked on the Spec An. Jackpot - +10 dBm out at 10224 MHz. Now simply reconnect everything back up and we had a frequency stable signal on 10 GHz, apart from the variations in the FT-817 IF.
Many thanks to Ralph for his assistance & encouragement.
So any others out there with a WhiteBox system might consider a similar approach. I know that there should be at least 16 in this country, as I imported that many & distributed them to interested amateurs at my cost price.
If I find the time, I might organise some photos to add to this brief description.
Peter VK3PF