NRGkitz or Veronica 50mW circuit diagram

[BlackBeard]

Interestingly, a lot of mini tx-boards are shown to me on Aliexpress recently. For example this one called "RF-02FM". Sadly, it's not the Veronica 50mw design but uses two 9018 and one 9014. 2€ would be crazy cheap for a usable driver board.

https://a.aliexpress.com/_EvdBQTL

[1608cc]

Colpitts oscillator, without varicap - output will be mixed AM and FM. Modulation straight on transistor , so won't be deep of because low delta voltage / delta capacitance of junction ratio. Just a more complicated bug device , only additional output separating stage is a pros.

[BlackBeard]

Colpitts oscillator, without varicap - output will be mixed AM and FM. Modulation straight on transistor , so won't be deep of because low delta voltage / delta capacitance of junction ratio. Just a more complicated bug device , only additional output separating stage is a pros.

Dziękuję. Mam jeszcze pytanie

I'll write it in english though so that everyone can understand it. If I would want to connect the Pira PLL to the NRGv6 design, to where do I need to connect the input and output of the PLL? I'd guess that a small capacitor (1-10pF) after L1 could be used for the connection to the PLL's input. The PLL's output should be connected to VD1/VD2? Maybe using 100 nF parallel and 10kO in series for filtering and more stability? I haven't really got a clue though

[yellowbeard]

Blackbeard
Our friend Sinus Trouble has done something similar with an NRG 1 Watt:
https://www.radionecks.co.uk/viewtopic.php?t=275
Circuit diagrams are on page 4...

[1608cc]

Can do something similar to my design:

https://www.radionecks.co.uk/viewtopic.php?t=3602

obraz_2024-11-03_220338979.png

EDIT: This solution is good only for sample & hold detector. When use digital you will get noise in spectrum... It uses same varicaps for modulation and PLL, so same linearity for 88 and 108 is achieved. Can't put capacitor after 10k to make RC filter for digital phase detector, because it cut high frequencies of audio. S&H detector in SAA1057 gives clean signal without any filters.

[Zealmclazy]

I have this 50mw but doesn't take frequency...tuning its okay

[Zealmclazy]

R30 resistor burnt

[Zealmclazy]

What color coding is this?

[shuffy]

Hard to see if the 3rd band is brown or black but since it's burnt like that I'd say it's 47R. I binned more through-hole 47s burnt like that than I care to remember. On your PCB photo though, it looks like R30 is 4k7, but I can't see the labels too clear. I can't advise further unless I can see the circuit diagram though, sorry.