NRGkitz or Veronica 50mW circuit diagram

[Gigahertz]

Just wondering if any of you guys have a copy of either the Veronica or NRGkitz 50mW transmitter design.

[teckniqs]

I haven't but back in the day I heard it was a decent little kit and works very well for what it is.

[Gigahertz]

Had both versions years ago and they were decent units. Just wanted a evening project for a bit of fun.

Remember Kanga had a brief encounter with NRG but just spoken to the guy to see if he had any documentation left but it all went on to guys in London and Blackpool

[1608cc]

Many years ago Polish pirates made their own version called "NRGv6". It's better than original





Standard version :



Micro version :

[Gigahertz]

1608cc, top man thank you

[radium98]

done a few years before .two bf494

[Bton-FM]

It is in the file

[Albert H]

I used to build something similar, but using a pair of FETs to really lightly load the tuned circuit. I also experimented with etched coils, but the best results were obtained with a single 12 turn coil, with taps every two turns. The coil was fiddly to make, but when you've made a couple of them, you get the hang of it. The oscillator is remarkably stable and very clean. It's a sort of first cousin of the "Kallitron" oscillator, which I first saw in a G2DAF communications receiver design. The basic version of the circuit was stable to within 100 Hz for an hour at 30 MHz, but adding a "huff and puff" stabiliser was really worthwhile because it would then stay on tune indefinitely.

[Bton-FM]

where can I buy BF494's?

[radium98]

Bf495 bf199 all work

[Bton-FM]

Thanks radium

[Gigahertz]

Might be missing it on circuit diagram on both but it states VCD1 on standard and on micro it has VC1 & VC2 but what values are theses ?

[1608cc]

VC1 : 22pF green film trimmer (Philips, BC components or now Vishay)

VD1, VD2 : BB809, BB409, BB109, BB329, BB529, KB109 (KV1310 only for ori NRG)

It is described in "wykaz elementów generatora.doc" in nrg6 folder

[radium98]

bb105 x 2 facing cathode ,bb204 any vhf varicap will suite .

[1608cc]

bb105 x 2 facing cathode ,bb204 any vhf varicap will suite .

Unfortunately not... BBxx9 has higher capacitance... There were tests and You need to put 2 BB105 (even 3 to cover all 88-108 band, if You want to use PLL) in parallel instead one BB809. And also sound quality will drop - only BBxx9 offers the best parameters (same loud on 88 and 108, low noise ratio). Circuit was originaly matched to BB809 not BB105/204.

[Albert H]

A friend of mine built one of these the other day (as a baby alarm) and just used reverse-biased LEDs for the varicaps. He painted them black to prevent light affecting the frequency (and adding mains hum to the modulation). He had to add a single transistor audio amplifier stage to get enough modulation from an electret microphone. He tuned it to 85 MHz and uses a Japanese band portable to monitor his new daughter!

[Bton-FM]

I've started building this.What ferrite bead is on the power input?How many turns should I put on it?

[Gigahertz]

A friend of mine built one of these the other day (as a baby alarm) and just used reverse-biased LEDs for the varicaps. He painted them black to prevent light affecting the frequency (and adding mains hum to the modulation). He had to add a single transistor audio amplifier stage to get enough modulation from an electret microphone. He tuned it to 85 MHz and uses a Japanese band portable to monitor his new daughter!

People round here are using PMR446 radios on VOX as baby monitors.

[yellowbeard]

I've started building this.What ferrite bead is on the power input?How many turns should I put on it?

It's a standard 3mm ferrite bead with 5 turns enameled wire on it.

[Bton-FM]

thanks yellow beard