The AM Forum
April 27, 2024, 09:34:46 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: 1 [2]   Go Down
  Print  
Author Topic: DX100B HIGH SWR ON AM  (Read 12486 times)
0 Members and 1 Guest are viewing this topic.
kb2vxa
Member

Offline Offline

Posts: 162


I modulate, therefore AM


« Reply #25 on: January 31, 2014, 12:31:28 PM »

Wa hoppin Lucy, you fogeh you bestdos  ohbin mit again? (;->) I may be a bit of a dummy load myself, but I don't see the difference between the AM position with the tubes removed and the CW position. In the latter the mod iron secondary is shorted, do you suspect the transformer? What about another test with the mutilator tubes in and the driver out? Could be something freaky going on with them, ah dunno.
Logged

73 de Warren KB2VXA
Station powered by atomic energy, operator powered by natural gas.
N2DTS
Contributing
Member
*
Offline Offline

Posts: 2307


« Reply #26 on: January 31, 2014, 12:36:45 PM »

If it was something in the modulator, you should see modulator plate current, no?
And the antenna tuna would have to be very high Q and tight to show high swr from something the modulator was putting out....
Logged
DMOD
AC0OB - A Place where Thermionic Emitters Rule!
Contributing
Member
*
Offline Offline

Posts: 1770


« Reply #27 on: January 31, 2014, 02:26:42 PM »

there never was any arcing..into the dummy load it does the same thing...tunes up fine in cw, but in am it has a high swr...the rig has not been hot switched, etc...

..sk..

You mean to say that into a dummy load in CW mode an SWR meter shows no VSWR, but in AM mode the same meter on the same dummy load does show SWR? How good is your meter and cabling?

Phil - AC0OB
Logged

Charlie Eppes: Dad would be so happy if we married a doctor.
Don Eppes: Yeah, well, Dad would be happy if I married someone with a pulse.NUMB3RS   Smiley
flintstone mop
Contributing
Member
*
Offline Offline

Posts: 5055


« Reply #28 on: February 01, 2014, 08:06:49 AM »

there never was any arcing..into the dummy load it does the same thing...tunes up fine in cw, but in am it has a high swr...the rig has not been hot switched, etc...

..sk..

You mean to say that into a dummy load in CW mode an SWR meter shows no VSWR, but in AM mode the same meter on the same dummy load does show SWR? How good is your meter and cabling?

Phil - AC0OB
I agree Phil...this thread is getting really confusing....I asked the OP to remove the mod tubes to see if the SWR problem stops in AM mode. I assumed the SWR is there when connected to the antenna. Now a dummy load is in the mix.
There can be no SWR into a dummy load. Freq range is from MF to light.......almost.
Someone else will have to sort this out......I'll be in the background reading.
Fred
Logged

Fred KC4MOP
Pages: 1 [2]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.033 seconds with 18 queries.