Author Topic: Reducing the power (5 watt PLL)  (Read 5971 times)

dotinga00

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Reducing the power (5 watt PLL)
« on: August 19, 2011, 11:10:56 am »
Dear Jan,

To reduce the power i found these instructions on the old forum

To make a 200 mW transmitter from the 5 W:
1) replace R7 with 1 uH or similar inductor
2) remove TR1, R9, L2, Q3, L3, C18
3) use two single wires to connect Q2 collector to C15 (1) and to connect C15 (2) to L4.


I have tried this, the power is now 100 mW. I need 200 mW. The output impedance of the Q2 is 75 ohm. Is it a good idea not to remove TR1?


Kind regards,

Marcel

Jan

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Re: Reducing the power (5 watt PLL)
« Reply #1 on: August 19, 2011, 12:28:03 pm »
I'm afraid the information from the old forum is final as this project has been closed long time ago. If the power is not sufficient, increase power supply voltage or decrease the R8 value a bit. However be careful not to overload the Q2 as in my opinion it already gives 200 mW but your measuring method provides bad result.

dotinga00

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Re: Reducing the power (5 watt PLL)
« Reply #2 on: August 19, 2011, 03:52:47 pm »
Hi Jan,

thanks for your answer, it helped me out. But where is the place to ask questions for "discontinued products". Thought only large companies had that policy :-(


regards,

Marcel

Jan

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Re: Reducing the power (5 watt PLL)
« Reply #3 on: August 19, 2011, 07:33:19 pm »
You may ask anything, this is a purpose of this public forum. But please observe a distinction between final product and a self made or self modified device that you make at your own risk. Any device built this way is unique, nobody can know it better than the one who has built it.