[1000mp] Strange bahaviour on 80 meters

Sun, 28 Dec 2003 17:23:37 -0500

Right, Vidi.  I should have mentioned that it always worked FB with a 
dummy load.  A real head scratcher.

73, Joe

Vidi & Hester wrote:

>Hi guys
>I also have this problem from time to time, especially on 21mHz.  When I
>first noticed it, it happened on 18mHz.  When switched to a dummy load the
>problem was not evident, which made me think that it could be something
>taking off causing  transmission out of  band limits, which explained high
>swr on resonant antenna and good swr into dummy load.  I confirmed this by
>listening around on an external RX - - - real rough spurious signal all over
>the show.  Switching rig off and letting it get back its senses always
>eliminates the problem and it would not happen again for months.  For this
>reason I have not consulted Yaesu yet.
>
>73
>Vidi, ZS1EL
>
>
>----- Original Message -----
>From: "Joe Giacobello" <[email protected]>
>To: <[email protected]>
>Sent: Sunday, December 28, 2003 4:17 PM
>Subject: Re: [1000mp] Strange bahaviour on 80 meters
>
>
>  
>
>>OK, Pete.  Well, Yaesu was clearly right:  the problem seemed to
>>diminish in frequency when I changed amplifiers.  However, the problem
>>manifested itself whether the tuner was engaged or not.  When I
>>originally complained to Yaesu about the problem, they couldn't
>>reproduce the behavior in their shop.  I had to send them a video tape
>>of the unit misbehaving before they believed me, and then they
>>conscientiously investigated the problem.  To their credit, they didn't
>>charge me for their efforts.
>>
>>73, Joe
>>
>>Pete Smith wrote:
>>
>>    
>>
>>>At 10:46 AM 12/27/03 -0500, Joe Giacobello wrote:
>>>
>>>      
>>>
>>>>...
>>>>However, even after Yaesu seemed to have solved the basic 15M SWR
>>>>problem, the SWR would unpredictably go haywire periodically.  Yaesu
>>>>worked on it again and concluded that the problem seemed to be
>>>>associated with the amps that I was driving at the time: a vintage
>>>>30S1 and a Viking Thunderbolt.  When I replaced them with a TenTec
>>>>Titan 425, my problems disappeared...for the most part.  I say for
>>>>the most part because every now and then, totally without warning and
>>>>for no obvious reason, the SWR will go haywire.
>>>>        
>>>>
>>>I haven't had the transient SWR problem with my Mark V, but after I
>>>modified my SB-220 for QSK, I discovered that my TS-930 didn't want to
>>>drive it without the tuner engaged on 10M.  Later, I got the Mark V,
>>>and discovered a similar problem with the drive on 40M, which again
>>>was cured by setting a single tuner memory and letting the radio
>>>extrapolate from there.  It was fine on 10; in neither case did the
>>>input SWR look THAT bad.
>>>
>>>I think Tom Rauch and others have commented that these older
>>>amplifiers that were designed for tube exciters with adjustable pi
>>>networks can be quite cranky with newer solid-state rigs, depending on
>>>a lot of design variables.  I once tried to substitute a much shorter
>>>input cable, and my TS-930 didn't like at AT ALL.
>>>
>>>
>>>73, Pete N4ZR
>>>Happy Holidays
>>>Check out the World HF Contest Station Database at
>>> www.pvrc.org/wcsd/wcsdsearch.htm
>>>
>>>
>>>
>>>_______________________________________________
>>>List Moderator: Richard Lubash N1VXW
>>>1000mp mailing list
>>>[email protected]
>>>To Change Options or Unsubscribe:
>>>http://mailman.qth.net/mailman/listinfo/1000mp
>>>
>>>
>>>      
>>>
>>_______________________________________________
>>List Moderator: Richard Lubash N1VXW
>>1000mp mailing list
>>[email protected]
>>To Change Options or Unsubscribe:
>>http://mailman.qth.net/mailman/listinfo/1000mp
>>    
>>
>
>_______________________________________________
>List Moderator: Richard Lubash N1VXW
>1000mp mailing list
>[email protected]
>To Change Options or Unsubscribe:
>http://mailman.qth.net/mailman/listinfo/1000mp
>
>
>  
>

--- StripMime Report -- processed MIME parts ---
multipart/alternative
  text/plain (text body -- kept)
  text/html
The reason this message is shown is because the post was in HTML
or had an attachment.  Attachments are not allowed.  To learn how
to post in Plain-Text go to: http://www.expita.com/nomime.html  ---