FT736R.6
Subject: FT736R - VHF Attenuator Mod
A little trick to built in an RX-Attenuator in the FT736R (VHF Band)
Heìlo FT736 fans,
Using a preamp in the VHF Band causes sometimes trouble with noise on
this band. The S-Meter readout 2-4 without any signal. The AGC is
working only to reduce the noise.
A simple trick decrease the sensivity for about 6 dBm.
Look in the schematic-diagramm 144 MHz MAIN-UNIT. The first RX-Stage
is at the left side of the sheet. Locate the transistor Q01 3SK122L
and look at the source-resistor R02 (47 Ohm). A second resistor with
the value 1.2 KOhm in series with R02 decrease the sensivity for 6 dB.
Using the preamp-switch (this switch has a free row) You can easyly
switch between attunation and normal use by making a bridge over the
new 1.2 KOhm Resistor with this contacts.
I think, this trick is not a excellent way of a RX-Attunator, but it
works ufb here in my rig.
By the way, remember of loosing warrenty bù modify Your rig ! I am not
responsable for failures after modification !
Vy 73 de Guenter DD9ZO
SOURCE: The QRZ Windows Ham Radio CDROM |
