A simple SW AM reaceiver, most of them can be brought to air band,
just replace PVC2J with FM gang and decrease the turns of oscilator
coil mentaining the difference of 455 kcc. In totall there are three
coils in single core for bandpass, oscillator and
mixer/downconverter. One just needs to replace the gang and the
antenna coil. However the selectivity/stability is not so good. For
more professional design I saw somewhere in SMOVPO website. Adding
a jfet preamp is always better it also increases sencivity. I have
also seen a design somewhere by our very own VU2ZAP OM Raj, if I am
not wrong. Which has also AGC stage, an advance design using SA 612
but needs some alternations for VHF mostly with inducters one can
understand easily, this is the best design ever seen. 73's VU3SXT
message typd frm
mobile phone in local train plz dnt mke issue with mistakes.
On 02/03/2011, SATYAN VU3MES <satyansarath40@ovi.com> wrote:
> hi
>
> if some one wants to listen only to airband transmission on vhf, there is
> a very simple way by which you can do it provided you have a decently
> sensitive fm radio. the technique is to listen to the image frequency by
> peaking the IF transformers which are usually 10.7 mhz. if i want to
> listen the chennai area control on 118.9 i should tune to 98.5 which is
> less by double the IF frequency.
>
> i used to try this method long back when i was not having a proper radio
> with airband coverage. the only drawback is the coverage will be upto
> 128.7 mhz and not above that.
>
>
>
> 73s de VU3MES
> chennai - india - qth location website.
> http://www.findu.com/cgi-bin/find.cgi?call=vu3mes
> http://www.qrz.com/callsign/vu3mes
> http://www.satyansarath.param.mobi [mobile web page]
>
>
>
> ----- Original message -----
> From: "Raj‎" <vu2zap@gmail.com>
> To: HamBrewers@yahoogroups.com
> Subject: RE: [HamBrewers] Air Band Receiver
> Date: Wed, 02 Mar 2011 20:39:26 +0530
>
>
>
> A regen Rx with a front end pre-amp is quite OK. This stage blocks the
> regen oscillation.
>
>
> SA602/612 NE602/612 Etc.
>
>
>
> I once constructed Tony Van RoonÂ's rx and it worked. Apart from that
> I have built couple of Regen Rxs – they tend to receive all
> conversations simultaneously. Also, they are very dangerous because
> they radiate via the antenna causing QRM and should not be used
> anywhere near Airport – they can cause serious qrm to aircrafts in
> range also.
>
>
>
> Rajesh K
>
> KC2KBY/VU3RGK
>
>
>
> -----Original Message-----
> From: HamBrewers@yahoogroups.com [mailto:HamBrewers@yahoogroups.com]On
> Behalf Of Vignesh Kumar
> Sent: Wednesday, March 02, 2011 9:18 AM
> To: HamBrewers@yahoogroups.com
> Subject: [HamBrewers] Air Band Receiver
>
>
>
>
> Hello Friends,
>
> I want to build a Simple Air Band Receiver. Can
> anybody suggest AM receiver ICs for VHF band?
>
>
>
> --
> Raj, VU2ZAP
> Bangalore, India.
>
>
>
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