Dr Ronald Stiffler SEC technology

[NickZ]

   erfandl:   My 13.5MHz crystal oscillator is pictured below. It runs best using the 7.2MHz crystal, or a 12.000MHz crystal.
   The diagram (below) was taken from one of Lidmotor's videos.
   I've provided for two outputs, one for the leds, and another for future power looping, back to the input.

[mikrovolt]

The projects getting better
https://www.slideserve.com/selah/bifilar-wound-toroids-session-2
https://www.bamlog.com/diyxfmr.htm
https://www.abcelectronique.com/annuaire/montages/cache/3560/melangeur-transmetteur.html

Hobbyist approach Doug DeMaw has good explanation hands on approach.
Starting on page 45 crystal circuits, impedance, vfo buffer, using small ferrite beads, ect

http://www.n5dux.com/ham/files/pdf/W1FB%20-%20QRP%20Notebook.pdf

[erfandl]

   erfandl:   My 13.5MHz crystal oscillator is pictured below. It runs best using the 7.2MHz crystal, or a 12.000MHz crystal.
   The diagram (below) was taken from one of Lidmotor's videos.
   I've provided for two outputs, one for the leds, and another for future power looping, back to the input.

thanks NickZ. how to provide output to input for looping ? do you connect 2 diodes to battery ?

[gyulasun]

Gyula,

thanks for the comments, i will digest them later this weekend.
The question you have i can answer, as the current pulled by the PS at 17.8V was 2.2mA.
Measuring the current from the battery feeding the oscillator was fouled up by RF? as i could not get
a correct reading.
itsu

Hi Itsu,

2.2 mA forward current at 17.8 V: that is rather low. It means the individual SMD LEDs on those boards are already able to give brightness you show in the video from 2.4 - 2.5 V individual forward voltage levels.

Specifications on the 5050 LED chips:
https://www.superbrightleds.com/moreinfo/surface-mount-smd/warm-white-5050-smd-led-120-degree-viewing-angle-6000-mcd/317/1249/

For any single SMD LED chip (that your boards include) the forward voltage is written to be 3.2 V at 3x20 mA current this is because any single chip includes 3 LED diodes integrated and connected in parallel within any chip.

The parallel connection of two series strings on a board having 7-7 such chips reduces the specified 7x3.2V= 22.4V at 60 mA: you made a test at 60 mA and the voltage was 20 V from the PS or your another test done at 67 mA needed 20.3V (7x2.9V), this is possible and comparable. The resulting reducement in forward voltage for parallel connected LEDs is similar to that of Zener or for just normal diodes.
I do not think your earlier RF current measurements were false (around 50 mA taken from the 12.5V battery), you confirmed this with an analog ampermeter too. Back then the LED board was driven by its back plate via a single wire from the L3 coil, now you drove the LED board from an AV plug which was driven from the 3rd coil of a 3 coil setup. Also, the capacitive coupling you created between the wire from the input to the 3 coils and the PCB plate has an unknown pF value and its capacitive reactance reduces the RF voltage coming from the tank.

OR you meant input current measurement problems in the present case when you drive the 3 coils by the oscillator?

Thanks,  Gyula

[gyulasun]

Hi Slider,

First thing firsts: just test the oscilloscope and the probes with the built-in 1 kHz square wave output I assume you have in the front face (I do not know this scope type in detail).
Then if the scope is okay, then carry on exploring the waveforms from earlier known circuits. Then you can conclude something.