Measuring this way will NOT show if the radio is
splattering or not.
Instead measure the actual RF envelope by setting
the radio up as you normaly would have it during
a QSO.
Set the analyzer to something like 200 Hz bandwith,
max-hold cont-sweep 10 or 20 Hz 5-10 sec´s.
Run radio into a dummy load and sniff RF into the
analyzer, make sure analyzer doesnt get overloaded.
Again, a 2-tone test measuring 3rd/5th order IMD
will NOT show you if the radio is splattering or not.
Would be interesting if someone would measure a
FT1000MP field this way at lets say power levels
50/100/150 Watts.
Measuring this way going from 50W to 100W will increase
splatter 5 kHz away with around 20 dB, just wounder
how much it would increase going from 100 to 150,
well I´m sure it will be horrible so maybe I wouldn´t
like to know.
73 Jim SM2EKM
-------------------------------
Thomas Giella KN4LF wrote:
14070 kc 100 watts 3rd order -31.9 5th order -45.1
14070 kc 150 watts 3rd order -31.8 5th order -44.9
14070 kc 200 watts 3rd order -31.3 5th order -44.4
73,
Thomas F. Giella, KN4LF
Plant City, FL, USA
Grid Square EL87WX
Lat & Long 27 58 31 44N 82 09 51 98W
PODXS 070 PSK31 Club Member #349
KN4LF Solar Space Weather & Geomagnetic Data Archive: http://www.kn4lf.com/kn4lf5.htm
----- Original Message -----
From: Thomas Giella KN4LF
To: All about Yaesu 1000mp
Sent: Friday, August 06, 2004 10:17 AM
Subject: Re: Mark V Field Power Output Mod
Morris et all,
I used an HP8563E spectrum analyzer and some other equipment to measure spectral purity at 100 watts, 150 watts and then at 200 watts on the V Field.
There was no discernable spectral purity degradation at 150 watts and a very minimal amount of degradation at 200 watts and still well within FCC requirements.
73,
Thomas F. Giella, KN4LF
Plant City, FL, USA
Grid Square EL87WX
Lat & Long 27 58 31 44N 82 09 51 98W
PODXS 070 PSK31 Club Member #349
KN4LF Solar Space Weather & Geomagnetic Data Archive: http://www.kn4lf.com/kn4lf5.htm
----- Original Message -----
From: morris wideman
To: All about Yaesu 1000mp
Sent: Friday, August 06, 2004 7:49 AM
Subject: Re: [1000mp] Re: Mark V Field Power Output Mod
Hello
Im curious as to how you checked the spectral purity of your modified radio?.
Finals that are operating at 12v not 30 are going to be much more likely to generate spurious emissions if they are overdriven.
WA4MIT Morris
----- Original Message -----
From: "Thomas Giella KN4LF" <kn4lf@tampabay.rr.com>
Date: Thu, 5 Aug 2004 23:45:07 -0400
To: "a Yaesu E-Group" <yaesu@contesting.com>,"a FT-1000MP eGroup"
<FT-1000MP@yahoogroups.com>,"a 1000MP QTH e-List" <1000mp@mailman.qth.net>
Subject: [1000mp] Re: Mark V Field Power Output Mod
> My original post below has stimulated allot of controversy and posts. I stand by what I already said:
>
> .....I've tested the rig extensively at 175 watts on CW and RTTY and have suffered no component failures, overheating, etc. and no transmit spectral degradation. Of course like all mods. make it at your own risk.....
>
> I look at it this way. In the original spirit of ham radio I'm not afraid to open up my modern expensive rice box, to experiment and modify. In my original post I never mentioned operating my V Field at 200 watts but it did hold up very well with no overheating etc. at 175 watts on CW and RTTY, as an experiment. Why did it hold up so well? It's because the rig is better engineered and has better specs. then advertised and a certain amount of "appliance operator" headroom is built in.
>
> Am I stressing the rig? Maybe so but if it blows up I'll fix it and/or buy another one. One ham posted in response to my original post, to paraphrase, "Real Ham's understand how electronics work and don't turn up the power on their rig". I say "Real Ham's" are not afraid to experiment.
>
> In any event, in my day to day operations I never run my V Field above 125 watts. I originally tweaked up the power output because from the factory my V Field only put out 90 watts on 160 meters and I needed 125 watts to drive my old linear to 800 watts.
>
> 73,
> Thomas F. Giella, KN4LF
> Plant City, FL, USA
> Grid Square EL87WX
> Lat & Long 27 58 31 44N 82 09 51 98W
>
> PODXS 070 PSK31 Club Member #349
>
> KN4LF Solar Space Weather & Geomagnetic Data Archive: http://www.kn4lf.com/kn4lf5.htm
> ----- Original Message -----
> From: Thomas Giella KN4LF
> To: a Yaesu E-Group ; a 1000MP QTH e-List ; FT-1000MP@yahoogroups.com
> Sent: Monday, August 02, 2004 6:28 PM
> Subject: Mark V Field Power Output Mod
>
>
> Justin et all,
>
> The Mark V Field power modification is simple but it will attract naysayers that will warn of power supply damage/failure, finals failure, degraded transmitted spectral purity, etc.
>
> Pop the top and bottom covers. Gently turn the rig upside down on a hard surface with the front of the rig facing you. There are three boards visible. One is the "Control" board on the left side, the "AF" board on the back right side and the "IF/Filter" board on the front right side. Go to VR3003 on the AF board and turn it clockwise. It's marked "RF Power" (I think it was). Fully clockwise gives you 190 watts in the CW mode on 14200 kc, 200 watts on 1845 kc and 180 watts on 28400 kc. Of course connect an antenna with low VSWR or a good dummy load.
>
> I've tested the rig extensively at 175 watts on CW and RTTY and have suffered no component failures, overheating, etc. and no transmit spectral degradation. Of course like all mods. make it at your own risk.
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