Re: LF: My 500kHz 10W Transverter is almost ready

[Roger Lapthorn <rogerlapthorn@gmail.com>]

Hi Steiner (et al),

Have now updated the 472/500kHz transverter schematic and shown an additional LPF on the output, which I think is a good idea with a larger antenna (not needed with a loop or short, sharply tuned, Marconi. See https://sites.google.com/site/g3xbmqrp/Home/472khz-transverter .

73s
Roger G3XBM

On 20 October 2012 22:09, Steinar Aanesland <saanes@broadpark.no> wrote:

Hi Roger

Yes , I thought I saw a red and not a yellow one in your picture ;)

I believe you are referring to the C11 when you are writing "wrong value
of coupling cap" . What is the new value you propose to use instead of
470nF?

LA5VNA Steinar
loc:JO59jq
Mal and spam filtering: STRONG
www.opera.no

Den 20.10.2012 21:17, skrev Roger Lapthorn:

> Thank you for your kind words Steiner.
>
> There are a couple of errors on my schematic that I must correct (T50-2
> red, not T50-6 yellow in the buffer and the wrong value of coupling cap
> between the LO and buffer). I measured the harmonic output on a friend's
> spectrum analyser today. If you are not using a sharply tuned antenna like
> a loop or short Marconi (like me) then I recommend adding an additional low
> pass filter on the output. The one on GW3UEP's page would be ideal. (6n8s
> and a 15uH inductor).
>
> 73s
> Roger G3XBM
>
> On 20 October 2012 19:15, Steinar Aanesland <saanes@broadpark.no> wrote:
>
>>
>> Hi all,
>>
>> My 500kHz 10W Transverter is almost ready (just a little cosmetic
>> remains) .
>> https://dl.dropbox.com/u/16381257/MF_transverter.jpg
>>
>> A big thanks to Roger G3XBM for this nice and simple design.
>> https://sites.google.com/site/g3xbmqrp/Home/472khz-transverter
>>
>> I don't have the the right equipment for testing the output, but the 15W
>> 50ohm dummy load is getting really hot .
>>
>> The big issue now is the antenna. My first thought was a kind of a T(
>> top hat)-antenna, but I have a loop antenna about 80 meter in
>> circumference and 6/7 meter above the ground . What about using the loop
>> as a capacity on the top of a vertical or using the loop as an ordinary
>> loop antenna for 600m ?
>>
>> --
>> LA5VNA Steinar
>> loc:JO59jq
>> Mal and spam filtering: STRONG
>> www.opera.no
>>
>>
>>
>
>

-- 
 http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
https://sites.google.com/site/sub9khz/
http://qss2.blogspot.com/

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