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If I reduce the current in the transistor output using the 1K variable resistor, the transmission distance does not change at all, although the BFR96 gets cold....The transmission distance should decrease, but it does not. I use rg58 coax and homemade dipole ...
So the only output of the...
Thank you everyone for your answers!!!!
I hadn't soldered well a capacitor at the loop filter, so it didn't work well!
Now the transmitter locks from 87 to 100.2 MHz which is enough for me! The sound is really clear, I had a grounding problem but I fixed it..
Thank you! :)
Thank you very much! This means that the "LOCK" stays forever, and it's normal :)
The helicopter sound cannot be due to the vco being on the edge of oscillating, because I've tried many different coils and the problem continues....
Can I change the 100pF capacitor in series with the varicap...
It works!!!
The pll locks now!!! The problem was the burned TSA5511! I ordered a new one, I put it on the board an now the pll locks and I can hear the signal on a radio!
However there is a problem: If it gets locked, it never unlocks! When it locks, if I remove the coil from the board, the...
Today I was told that PIC16f628A has problems with portA as digital output, and maybe this is the reason why it doesn't communicate with the TSA5511...
Should I try with the PIC16F628 04/P ? What are the differences?
The project has also 3 hex files for PIC16F84.....
There is an oscillation there, as I measured, so everything is ok here.
Furthermore, I've tested 5 different hex files that are available for this project, and every program has the same behaviour.
This is interesting: When I first connected the project to power supply, the RED led turned on...
OK, this may help you:
This is the exact board I made. The output of 78L09 is connected to a 78L05 which supplies the TSA5511.. So there is a connection between 78L09 and TSA5511.
However, let's just forget the 78L09 problem, because it is solvable if I don't ground the pin 10 of the...
sky_123 thank you for your answers! :)
When I remove the TSA5511 from the board, the 78L09 supplies 9 volts without getting hot.
If I put again TSA5511 on the board, the 78L09 supplies now ~4 volts on its output, so it gets hot!
However, if I don't solder the pin 10 of the TSA5511 on the board...
This circuit diagram is what I am using.. But the output stage with 2SC1971 is different for me, I don't use this transistor, my version is slightly different.
Everything is almost the same, instead of the transistor in the oscillator stage. I use BF981.
I finally got my multimeter back and measured the voltage at the pins of the TSA5511.
I get ~5V at pins 6,7,8,9,10,11,12,13!! This behaviour can't be normal! Why does this happen?
The leds stay off and the 78L09 gets hot because of this.
1) Does this mean that the TSA5511 does not communicate...
Thank you everyone for your answers!
A friend took my multimeter till tomorrow so I can't measure the voltage at pin. 11 right now.. However I'll check it tomorrow
Which transistor do you think that it's burnt?
I tested a few more things today. At first, I unsoldered the BC557 transistor from...
First post here! Nice to meet you!
I recently made the pll fm transmitter 300mW Rdvv as it is here: https://www.3-mtr.info/shareware/RDVV%20300mWatt/
The pic, the buttons, the lcd are working perfectly! However the TSA5511 chip gets extremely hot and the PLL cannot lock.
I found out that it...
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