6600 XVRT drive level

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  • Updated 2 years ago
put radio on test since i unpack it for make sure all is ok before put on remote site
have try very hard to find flay but ,so far only 2 point

but i found that 2 point 

1-) XVRT  drive level is not as specified  ,set it for +15dbm  and radio output  +11.2dbm
     test is done @ 28.2Mhz     this may a doc issue ??

2-) 6m  IMD , not want to put number here  but seem very variable whit different drive level.
     full power  is good  but around  50% is not so good  ,please note that test is make @12.0V
     but i agree that  "ALL HF" radio barely make IMD limit on 50Mhz .. 

i take the opportunity of the -20 Celsius outdoor temp to test the 6600 in the cold ,it worked flawless ;-)  , but sill put it on heated box for run it on specification temp range 

good job on birdie to i found only 3 strong one  ~24,57Mhz  and 2 other bellow 160m
absolute noting from 28.0 to 28.5 were all transverter work is usually done ;-)

Marc L. 

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Marc Lalonde

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Posted 2 years ago

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Mack McCormick, Elmer

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We worked on the transverter output levels on the Alpha team and thought we had them solved. I'll check and if it's still a bug I'll submit a bug report.

The radio is recommended to run at 13.8 VDC and if you run it at 14.5 VDC you will have even less IMD. I've checked with the Flex engineers and you'll do zero harm to your radio at 14.5 VDC. 


Alpha Team
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Marc Lalonde

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Hi Mack   

i redo the XVRT level test @13.8V and still +11.2dbm  ,for now i re-calibrate my amp for match +11.2db

as for IMD  ,13.8V hep for sure , will see if i have time to redo test
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The 6400/6600 Hardware Reference on page 14 shows a maximum XVTR power of +10 dBm while page 36 mention a maximum of up to +15 dBm.  My 6600 produces 10.9 dBm maximum at 28.2 MHz.  On 40M the output is about 13.4 dBm.  On 160M it's 15.0 dBm.  And, on 630M it's 14.8 dBm.  A last check on 50.125 shows 10.1 dBm.  So, it appears the XVTR output is higher on the lower frequencies but always at 10 dBm and above at 6M and below.

Hope this comparison helps!
Chuck, AE4CW
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Marc Lalonde

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ok but on setup on XVRT page it "allow" to put it to +15dbm  ;-)
but normally the XVRT is leveled  ans stable over frequency !

i wait for a updated  hardware manual that cover the 6600 / 6400