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Who’s the builder ?

Posted: Tue Jan 07, 2020 6:17 pm
by Markybhoy182
Hi, there trying to find out more info on who bulid my latest tx, I’ve just got it, it’s the 4 watt version of nrgkits pll pro 3 as they done a fantastic job! Ive try to email the seller on eBay but still no reply, on the package 📦 return to sender say andy B ?, ring any bells to any one here?., I have the 1 watt version boxed that mr stephen moss build for me about 16 years ago , cud be longer,runing with the 25 watt amp from Veronica , the 1 watt is still as rock solid i can still remember being on the phone to stephen with the build at the time , I also had a few of the vfo 5 watt back in the day :tup

Re: Who’s the builder ?

Posted: Tue Jan 07, 2020 11:31 pm
by Albert H
Stephen and I used to omit the LEDs from the board if it was going into a case. We had a little adaptor PCB that had the mod socket and four LEDs on it. The LEDs were Power (Green), "RF Out" (Green), "Out of Lock" (Red), "Locked" (Green). There was also a version for battery power, that had a red LED for "Under Voltage". The idea was that a row of green LEDs showed that all was well. The LEDs were connected to the board down a piece of "rainbow ribbon" cable.

At power-up, the "Power" LED would light immediately, with the red "Out Of Lock" lit as well. The red LED would begin to flicker as the PLL went towards lock, then the red would go out, and the "Locked" LED would illuminate. After a further couple of seconds, the RF output LED would light. There was a simple "out of lock power-down" circuit that prevented RF getting to the final transistor until the PLL had been locked for a few seconds.

Stephen also had PCBs etched for the power supplies and Voltage Regulators.

We were working on an update to the PRO III at the time of his death. We planned to have a metal flange across the whole board, that would provide both heatsinking for the output transistor and the regulators, and a screen to separate the output filter from the rest of the board. We also planned to offer rotary frequency setting switches, and I did some work on adding switched capacitors to the VCO to eliminate the trimmer capacitor. I also added a second dual varicap with a voltage scaling resistive network to give the same modulation sensitivity - without adjustment - across the band. We also experimented with etched VCO coils (on a sub-board that mounted vertically on the main PCB), but found that the Q was low and the board tended to be more microphonic than conventional coils.

Re: Who’s the builder ?

Posted: Mon May 18, 2020 2:24 pm
by 3metrejim
Very similar to one of mine built around 14 years ago, except mine has liberal use of tin-plate, mostly around the home built PA and filter, high SWR cutout (for idiot proofing), and a 'not-very-good' (experimental) stereo encoder that I constructed myself. I also drilled a grid of holes to allow air in, rather than use a mesh. The rig was somewhere on a Spanish island, if I remember correctly.

Re: Who’s the builder ?

Posted: Tue May 19, 2020 10:03 pm
by rigmo
I do no like this dinosaur at all!

Re: Who’s the builder ?

Posted: Sat May 23, 2020 1:57 am
by Albert H
You can "not like" the PLL Pro III "dinosaur", but it worked very well, giving about 5 Watts across the band. The carrier was very quiet, with no synthesiser noise at all. It used components that you could buy anywhere in the world. It was on a large PCB to make it really easy for home constructors to put together. It was entirely reliable and was used as the driver in many very big transmitters!

A friend of mine tried a Broadcast Warehouse PLL+ to drive a very big (multi-kilowatt) valve PA. He could not get rid of the hum and instability due to the "at frequency" design of the BW board. He took a Pro III board to site and had no further problems!