Heathkit HA-14 - Service and Technical Support

FE et
) Remove the inner leads of the two coaxial
eables and the black wire from lug 1 of the
RCVR jack,-Connect these wires to lug 1
of the terminal stYip (S-3),
Connect a 3-1/2" black wire from lug 1 of
the RCVR jack (S-1) to the circuit board foil
near terminal pin 7 (S-1),
~~
( ) Change the lettering of this jackfrom RCVR
to ALC, A grease pencil or marker pencil
works very well for this,
This completes the modification of your Trans-
piver,
SWR MEASUREMENTS A
) Connect the Linear Amplifier to the exciter
and the antenna, Do not turn on the Linear
Amplifier, thus permitting the exciter to
feed through the Linear Amplifier to the
antenna,
‘ ) Place the Linear Amplifier METER switch
in the FWD position,
Page 35
( ) Load the exciter to full output, The meter
of the Linear Amplifier may be used for
this purpose, as it will function in both
the REL PWR and SWR positions without
the Linear Amplifier being turned ON,
( ) Adjust the METER SENS control of the
Linear Amplifier for a SET (full-scale)
indication on the meter,
() Turn the METER switch to SWR and read
the standing wave ratio directly from the
meter (1 to 3 scale),
NOTE: SWR checks can also be made with the
Linear Amplifier operating at full power (1000
watts); however, due to the nonlinear character-
istics of crystal diodes in the SWR circuit, the
most accurate SWR readings are obtainedat low
power (70 to 100 watt) levels using only the
exciter, If the exciter alone will not give full
scale relative power readings, the Linear Ampli-
fier may be used, however, limit the drive from
the exciter to no more than necessary,
OPERATION /
3B OPERATION
( ) Connect all leads between the Linear Am-
plifier, the exciter, and the power supply.
(_) Connect a dummy load or antenna to the
RF OUTPUT socket on the Linear Ampli-
fier,
‘, ) Set the exciter to the desired frequency,
( ) Set the Linear Amplifier BAND switch to
| the desired band,
\ ) Turn on the exciter only, Load the exciter
in a normal manner at the desired fre-
quency, NOTE: With the Linear Amplifier
turned off, the exciter output is fed through
the Linear Amplifier to the RF OUTPUT
jack, The FWD and SWR functions of the
Linear Amplifier meter can be used in load-
ing the exciter,
( ) Check the SWR of the antenna system as
described previously, Coes. aleove) te
( ) Reduce the drive level of the exciter toa
minimum,
() Turn on the Linear Amplifier and apply a
small amount of RF from the exciter, Peak
the TUNE control for maximum REL PWR
on the Linear Amplifier meter,
( )
Switch
the
exciter
for
SSB
operation
and
set
the
microphone
level
to
the
desired
level,
This procedure of tuning the Linear Ampli-
fier should take only a few seconds, after you
go through it a few times, The Linear Ampli-
fier is now loaded for operation at maximum
input power,