[amsat-bb] Re: Arrow 10W Duplexer Performance Measurements

[Edward Cole]

Last winter I temporarily set up a 2m 1/4 WL ground plane with 432 
preamp (similar to the ARR) and powered it with a single 9v 
"transistor" battery.
Most of the Gasfets use regulators to lower 12v to a usable working 
voltage.  Or for a long-term solution series two 9v batteries and add 
a LM7812 regulator.  Simplest wx-tight enclosure for an ARR preamp is 
a small zip-lock bag.  All small enough for hand-held Arrow setup.

73, Ed - KL7UW
BTW interested if Kenwood will come out with an upgrade for the TH7-G 
(had one and was great little radio)

At 04:01 AM 10/21/2009, Bruce Robertson wrote:
>I'm grateful to everyone who has contributed to this discussion.
>
>It strikes me that the greatest improvement we could make to hand-held
>yagis would be to somehow integrate a low noise preamp circuit very
>close to the 70cm port. I have an indoor-style ARR preamp that I've
>thought of connecting to the boom with cable ties. A powersupply using
>AA batteries and a DC to DC buck-boost chip from, e.g., Maxim, would
>keep the whole thing light. (Alternatively, I see that the max voltage
>for my ARR is pretty high: I might get away with a pair of Nicad '9v'
>batteries.)
>
>Like so much of amateur radio, it's more of a challenge of
>construction than anything else.
>
>Has anyone experimented with this sort of improvement?
>
>73, VE9QRP
>Bruce
>
>On Wed, Oct 21, 2009 at 8:21 AM, Allan Saul <allan at rfdesign.co.za> wrote:
> > Quite a lot of guys are using the handy Arrow Model 10W
> > duplexer for the handheld 146/437 antenna and mine arrived here
> > today so I thought I would put it on the network analyser
> > and see how it performs.....
> >
> > >From the Radio cable to the 2m antenna connector an Insertion Loss of
> > 0.75dB was measured with a rejection of 57dB at 70cm. The VSWR at 2m was
> > 1.24:1
> >
> > >From the Radio cable to the 70cm antenna connector an Insertion Loss of
> > 1.2dB was measured with an attenuation of 56dB on the 2m signal. The VSWR
> > at 70cm was 1.29:1
> >
> > The VSWR on the 2m port was 1.21:1 and on the 70cm port was 1.20:1
> >
> > For those guys wanting to look at the actual plots they can be found here
> > 
> http://www.rfdesign.co.za/default.asp?pageID=785423593&filePath=D:\SoftPage_V5\files\5645456\Download-Library\Amateur-Radio\ZS1LS\Mode-J-Filter
> >
> > 73's
> > Allan ZS1LS
> >
> >
> >
> >
> >
> > _______________________________________________
> > Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> > Not an AMSAT-NA member? Join now to support the amateur satellite program!
> > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
> >
>_______________________________________________
>Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

73, Ed - KL7UW, WD2XSH/45
======================================
  BP40IQ   500 KHz - 10-GHz   www.kl7uw.com
500-KHz/CW, 144-MHz EME, 1296-MHz EME
DUBUS Magazine USA Rep dubususa at hotmail.com
======================================