VEC-1220K/1230K/1240K/1280K Owner's
Manual
26
Antenna Lead
Power Supply
Key
J1
J2
J3
ANT
PWR
KEY
REC
J4
Crystal
Select
Power
VXO
Switch
Receiver
1
2
3
4
5
6
7
1. Crystal Select:
Selects calling frequency (Y1) and optional crystal (
not
provided)
.
2. VXO Tune:
Varies oscillator above and below crystal's "cut" frequency.
3. Key Jack:
1/8" mini-jack, accepts manual keys and most electronic keyers.
4. Power Switch:
Applies power to transmitter circuitry.
5. Power Jack:
2.1x 5.0-mm, (+) to center (-) to sleeve, 12-14 V @ .5A
6. Antenna Jack:
RCA, >1watt of RF into 50-ohms, 3:1 VSWR or less.
7. Receiver Jack:
RCA, routes antenna to receiver via T/R switch.
Receiver Hook-up:
You may patch most receivers directly into your VEC
QRP-CW Transmitter's
receiver
jack without risk of damage. Transmitter output
is typically 32 dBm and the energy reaching your receiver through the
T/R switch is normally 25 dB lower, or about +7 dBm. This is a very strong
signal, but a high-quality receiver with a wide AGC range can usually handle it
without blasting out the speaker! If you are able to leave the receiver on during
transmit, you'll enjoy the benefit of full QSK operation. This means you'll be
able to monitor incoming signals--and listen to your own outgoing signal--
simultaneously. If your receiver has an attenuator switch, turning it on will help
reduce the effects of overload. By the same token, if your receiver has a pre-
amplifier, you should turn it off. Receivers unable to limit speaker or headphone
volume over a wide range of signal inputs must be turned down or switched to
standby mode while you send.