----- Original Message -----
From: Steve Rawlings <[email protected]>
To: f6kaw radio club d'ivry <[email protected]>
Sent: Sunday, July 08, 2001 8:27 AM
Subject: QRP TX for 136 kHz
Hello Pascal!
I have updated the web-site with my current VFO circuit. My
previous VFO circuit for the Marathon did not work for all brands
of 2N3819, but the new circuit tests OK with all the FETs in my
junk box - so I am confident that the latest circuit will be
reliable. See
http://www.alg.demon.co.uk/radio/136/qrptx.htm
In the keyed pre-driver, I have reduced the value of the timing
capacitor across the 3.3k resistor from 22 uF to 10 uF.
I hope that the QRP TX does become a Club Project. Please do not
hesitate to contact me if I can help in any way.
With best regards,
Steve GW4ALG
Hello, Steve, and thanks a lot for the infos about ur qrp tx.....
I didn't have so much time last week to solder some components on board,
because holidays arrives soon (just next week, yippee !!!!!)....Never mind,
i will take some of them to prepare the little tx during holidays, and hope
it will be finished as i come back here to make the previous test !!!
i also finish the DF3LP loop with coax RG213, and made some test on
138.830 khz rx.... the BF245C preamp seems to work well, but i don't
understand something :
- with 7mhz dipole, no lead strapped, i receive DCF39 abt S0 and qrm....
- with DF3LP loop, preamp in alu case, when i connect the shields of the
loop, signal is abt S1....
- when i connect only 1 shield, and only the center of the other side,
signal is S5 and "util signal" seems strong...
-when i disconnect the two shield of the loop, signal is S7 to S9, and
"util signal" seems to be the same.. (just a little more noisy !!!!)....
I just don't know what to think !!!! any idea ????
i couldn't make more test on amateur signal because of my free
time.....
Best 73's to you and hope to hear you soon .....Pascal.....F5PNP....
http://f6kaw.free.fr
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