Hi Contesters,
While reading recent discussions on Heil & CAT problems with YAESU,
I got a feeling that nobody reads electrical diagrams any longer!
FT-1000 dual audio output for headphones is generated by pair of transistors
with 1 KOhm in emiter, supplied from +9V via 100 Ohm & 100 uF and biased by
100 kOhm . Assuming optimal colector current of 4 mA, such a stage gives
maximum of 16 mW output power in linear class A but to the 1 kOhm load.
This is about 100 times less (- 20 dB) than available from final audio 2 W
amplifiers. They use 1 uF coupling capacitors which makes nice 10 kHz
high-pass filter with standard 16 Ohms headphones and greatly rejects hum!
Yaesu CAT electrical interface consists of + 5 V emiter follower TX and
10 kOhm pull-up with diode in series for RX. Interfacing with RS-232
computer serial port can be done by directly connecting CAT TX output to
RS-232 RX input. Additional 3.3 kOhm resistor to the ground is recommended.
RS-232 TX output can be connected to CAT RX input via 3.3 kOhm serial resistor.
CAT input should be protected from RS-232 negative voltage by small diode of
1N4148 type with anode connected to the ground.
ICOM & Kenwood use inverted RS-232 levels and therefore need MAX-232!
I wish you a very good luck with Yaesu CAT protocols as they take ages to
service the simple computer request of radio frequency. FT-1000 is supposed
to do that fast with ROM version 6. Unfortunatelly, I am not able to get this
free of charge item in 6 month via K7JA!
73 de Mario, S56A, S57MM, N1YU, ex YU3EA, YU1PCF.
email: Marijan.Miletic@IJS.SI
>From Bruce Herrick <bdh@mixcom.mixcom.com> Wed Apr 20 14:39:46 1994
From: Bruce Herrick <bdh@mixcom.mixcom.com> (Bruce Herrick)
Subject: Dayton!
Message-ID: <199404201339.IAA19778@mixcom.mixcom.com>
The Society of Midwest Contesters would like to welcome all amateurs to our
9th Annual SMC Hospitality Suite in Rooms 1201-1203 at Stouffer's in
downtown Dayton. We will open around 8 P.M. on Friday and Saturday nights.
This year we are going to designate Room 1203 as the official CQ-Contest
Suite. We will have a sign-in sheet for all you internet types, as well as
the usual refreshments and camaraderie. Come and meet your fellow netters
and contesters!
SMC members take note: If you are interested in a special Internet badge,
contact me at one of the phone numbers below, or send me e-mail. Badges
will be paid for and picked up at the suite. Cost is unknown at present,
but will probably be 3 or 4 bucks. Order cutoff is Friday afternoon. Sorry
for the short notice - I've had trouble posting to the reflector.
Thanks, and see you all there!
73, Bruce WW1M & Gary W9XT
1994 SMC Suite Hosts
Bruce D. Herrick bdh@mixcom.com Home: 414.462.1270
Pryon Corporation Office: 414.253.5678
N93 W14575 Whittaker Way Fax: 414.253.2772
Menomonee Falls, WI 53051 PacketCluster: WW1M > NB9C
|