[hpsdr] Re Munin low output on 6m

[a.groff]

Kjell,
    Replacing the Capacitors and I can now get 115 watt at 50mhz and a 
bit more at 53mhz.

    However, at 28mhz I can only get 90 watts and less at  30mhz .. ( a 
lot less at 42 mhz ).
It appears to start going into saturation at about 75 watt at 28mhz.   ( 
I had 100+w at 28 before replacing the capacitors.)

   I think I shall try tightening up the turns on L4  (??? ) if your 
think that would help.

AL, K0VM




On 11/16/2013 11:04 AM, a.groff wrote:
> Kjell,
>    I have the Caps on order and will report back..
>    If the problem is in the final output transformer shouldn't the 
> t1-2 source current increase as driver is increased above saturation ??
>    At 40watts output ( below saturation ) the drive required for 40 
> watts out is basically flat from 160m thru 6m.
>
> AL, K0VM
>
>
> On 11/16/2013 3:30 AM, Kjell Karlsen wrote:
>> Hi Al.
>>
>> I agree that the problem might be one of the capacitors. All my 
>> problems with low power on 6 meter has been with the output 
>> transformer and components around it.
>>
>> Please report back when you have tested with new capacitors.
>>
>> 73, Kjell
>>
>>
>>
>>
>>
>> På Sat, 16 Nov 2013 00:33:28 +0100, skrev Bob Campbell 
>> <joan-bob at bigpond.net.au>:
>>
>>> ***** High Performance Software Defined Radio Discussion List *****
>>>
>>> Hi Al,
>>>
>>> Check caps C25 C26 C27 are all ok.
>>>
>>> Mine failed when I went to load it up on 6m, blew the cermic cap apart.
>>>
>>> As Kjell suggested in a previous post replace these caps with four 
>>> 220pf
>>> 500vw 1206 caps.  Since doing this mine has been ok.  I suspect with
>>> this mod the current is shared evenly between all 4 caps and the 
>>> circuit
>>> is much more stable and I have no trouble getting the desired output on
>>> 6m now.
>>>
>>> 73's
>>> Bob.c
>>> Vk4xv
>>>
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>>
>>
>
>


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