Re[2]: [Icom] Icom 756 PRO and Receive Antenna

Thu, 4 Jul 2002 17:18:10 -0600

Hello George,

Thanks for the help. Luckily it was something much simpler. Greg Ordy,
W8WWV, e-mailed me and informed me that the manual has the receive
jack and transveter jack locations reversed. When I plugged the
antenna into the correct jack it worked. The back of the radio is
labeled correctly but the manual has them reversed.  Due to the
location of may radio I was not able to read the markings on the back
of the radio and was going by what the manual said.

-- 
73,

Tom                            mailto:[email protected]
KQ5S

Thursday, July 4, 2002, 5:01:32 PM, you wrote:

GW> Tom, it sounds like you are pushing the correct buttons in the correct way.
GW> What may be wrong is that your receive antenna connection may be open
GW> inside the radio due to esxcessive r-f on the antenna.

GW> The Receive Antenna jack wiring goes through a network consisting of a
GW> voltage-sensitive resistor (like a MOV) to ground, then a series
GW> incandescent lamp and then a conventional resistor to ground. The output of
GW> this network then goes to an input LPF, etc.

GW> If you have access to a service manual, look on the RF Unit schematic and
GW> find the Receive Antenna connector. Follow that wiring to the network
GW> described above. The parts involved are R112 (the MOV), DS111 (the lamp)
GW> and R111 (the resistor).

GW> It is highly likely that the lamp has burned out and that is why you cannot
GW> get any signal from your receive antenna. 

GW> If you need more help on this let me know and I can give you the Icom part
GW> numbers in case you need to to order replacements. 

GW> 73/72/oo, George W5YR - the Yellow Rose of Texas         
GW> Fairview, TX 30 mi NE of Dallas in Collin county EM13qe   
GW> Amateur Radio W5YR, in the 56th year and it just keeps getting better!
GW> QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771 I-LINK 11735
GW> Icom IC-756PRO #02121  Kachina 505 DSP  #91900556  Icom IC-765 #02437

GW> "Tom (KQ5S)" wrote:
>> 
>> Hello,
>> Could someone be so kind as to tell me how in the heck I get the
>> receive antenna function to work.  I have tried connecting my receive
>> antenna to both the Antenna 2 connector and the Receive Antenna (RCA
>> Jack). I have tried about every combination of pushing and pushing and
>> holding the Ant button on the front of the radio. If the antennas are
>> hooked up to the antenna 1 and antenna 2 then the front ANT button
>> will select either.  When I push and hold the ANT button I get a RX/1
>> or RX/2 but I am not receiving anything.  When I hook up to just the
>> Receive Antenna jack I get nothing.
>> 
>> What am I doing wrong.  I want to be able to receive on one antenna
>> and transmit on the other.
GW> ----
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