| |
ZL3AI > APRDIG 01.09.06 06:42l 98 Lines 3236 Bytes #999 (0) @ WW
BID : 8697-ZL3AI
Read: GUEST
Subj: [APRSSIG] Vol 26 #31, 1/1
Path: DB0FHN<DB0FOR<DB0MRW<DK0WUE<I0TVL<IW8PGT<SV1CMG<7M3TJZ<ZL2BAU
Sent: 060901/0433Z @:ZL2BAU.#87.NZL.OC #:1388 [Waimate] $:8697-ZL3AI
From: ZL3AI@ZL2BAU.#87.NZL.OC
To : APRDIG@WW
Today's Topics:
1. RE: Homebrew transmitter (scott_at_opentrac.org)
2. Re: Homebrew transmitter (wa7nwp_at_jnos.org)
3. Re: Homebrew transmitter (Richard Amirault)
----------------------------------------------------------------------
Message: 1
Date: Tue, 29 Aug 2006 10:19:59 -0700
From: <scott_at_opentrac.org>
Subject: RE: [aprssig] Homebrew transmitter
>Ramsey occasionally has an SMT xtal transmitter listed, the "Rocket
>Tracker". I think it's $75 assembled, about $50 kit, and has around
>25mW or so output power. The crystal will put the unit at or near
>146.565 for T-hunt purposes, so you'd have to get crystals made for
>144.390 to get it on the APRS freq.
I've used the MR6, and built a clone board of my own, and even one with an
integrated OpenTracker chip. I got bored one evening and launched it with
a few 12" helium balloons, though.
The MR6 design is awful in terms of spurious emissions. It's basically a
broadband comb generator - I took one to a buddy at a local radio shop and
we checked out both the MR6 and my clone on his spectrum analyzer, and it
puts out AT LEAST as much power 12 MHz up from the intended frequency. I
think it was actually about 1 dB higher.
I could sell complete kits at a profit for under $20, but I can't in good
conscience market something that as far as I can tell doesn't meet FCC
requirements. I don't know how Ramsey gets away with it.
As for putting other crystals on it, I'd say do so at your own risk. A
crystal that gives you a frequency in the 2 meter band could also give you
a strong carrier on 121.5 - and 25 mW is enough power to risk a visit from
your local Civil Air Patrol squadron or search and rescue team.
Scott
N1VG
------------------------------
Message: 2
Date: Tue, 29 Aug 2006 13:00:48 -0500 (CDT)
From: wa7nwp_at_jnos.org
Subject: Re: [aprssig] Homebrew transmitter
>I got this crazy idea to build a 100% homebrew tracker for car and I am
>looking for plans for a xtal controlled transmitter on 144.390
100% Homebrew - GO FOR IT!
There are far too few homebrew projects these days.
It's the commercial ventures were there's no excuse for things like
transmit only trackers or half second txd's...
73
Bill - WA7NWP
------------------------------
Message: 3
Date: Tue, 29 Aug 2006 15:34:30 -0400
From: "Richard Amirault" <ramirault_at_verizon.net>
Subject: Re: [aprssig] Homebrew transmitter
----- Original Message -----
From: <wa7nwp
Subject: Re: [aprssig] Homebrew transmitter
>>I got this crazy idea to build a 100% homebrew tracker for car and I am
>>looking for plans for a xtal controlled transmitter on 144.390
>
>100% Homebrew - GO FOR IT!
>
>There are far too few homebrew projects these days.
That because unless you have a VERY well stocked parts draw to draw from..
it's costs MUCH more to home brew a piece of equipment than to buy it.
In this case, I would think, a used HT would work just fine for this
application.
Richard Amirault N1JDU
Boston, MA, USA Go Fly A Kite
------------------------------
aprssig mailing list
aprssig_at_lists.tapr.org
https://lists.tapr.org/cgi-bin/mailman/listinfo/aprssig
End of aprssig Digest, Vol 26, Issue 31
Read previous mail | Read next mail
| |
