I just reinstalled my Icom back into my vehicle after it being out for
several months, I was listening to 20 meters yesterday and tried to
get into a few of the pileups that were going on. A second or two in
keying up to ID my call, the radio shuts off. I also have developed
what sounds like a ground hum on VHF.

For an antenna I am using a Yaesu ATAS-100 with a AM-COM controller.
When tuning the antenna in, I get to very low SWR's on the meter, so I
don't think that it is a high SWR that is causing it. I have checked
all connections and they are tight, so any thing further I can check?

Thanks

Kevin
w0klh

On Wed, 02 Jun 2010 06:41:16 -0800, dave wrote:
Kevin W0KLH wrote:
I just reinstalled my Icom back into my vehicle after it being out for
several months, I was listening to 20 meters yesterday and tried to
get into a few of the pileups that were going on. A second or two in
keying up to ID my call, the radio shuts off. I also have developed
what sounds like a ground hum on VHF.

For an antenna I am using a Yaesu ATAS-100 with a AM-COM controller.
When tuning the antenna in, I get to very low SWR's on the meter, so I
don't think that it is a high SWR that is causing it. I have checked
all connections and they are tight, so any thing further I can check?

Kevin w0klh

High current DC connections can get oxide inside without loosening.
Disassemble, clean with gentle abrasives and alcohol, reassemble, coat
with petroleum jelly. You are connected directly to the battery, right?

Good points. I've found the IC-706 to be bloody all sensitive to
voltages under about 12.59999999V.

A friend of mine found the original "butt contact" fuse holder was the
culprit. He accidently discovered the cause during one frustrating
session when repositioning the power cable by clasping the fuse holder
bodies (there are 2 of'em, IIRC). They were quite warm to the touch.

My installation involves direct, 10 ga. wires to the battery posts and I
am using automotive, blade-style, in-line fuses. Even then, I sometimes
need to remove the fuses, clean the blades, re-apply silicone grease
around the body and reinsert them to get the problem to go away.

Even given all that, I cannot park and operate SSB for more than approx.
20 minutes before the other OP eventually reports terrible distortion on
my transmission. I never operate FM -- I can imagine what problems that
mode can inflict on this problem.

A pox on their house for rolling out a rig that works so poorly under
such minor under voltages. It would not be my choice for a rig to rely
upon in an emergency.

73
Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
* Killfiling google & XXXXbanter.com: jonz.net/ng.htm

Kevin W0KLH wrote:
I just reinstalled my Icom back into my vehicle after it being out for
several months, I was listening to 20 meters yesterday and tried to
get into a few of the pileups that were going on. A second or two in
keying up to ID my call, the radio shuts off. I also have developed
what sounds like a ground hum on VHF.

For an antenna I am using a Yaesu ATAS-100 with a AM-COM controller.
When tuning the antenna in, I get to very low SWR's on the meter, so I
don't think that it is a high SWR that is causing it. I have checked
all connections and they are tight, so any thing further I can check?

Thanks

Kevin
w0klh

High current DC connections can get oxide inside without loosening.
Disassemble, clean with gentle abrasives and alcohol, reassemble, coat
with petroleum jelly. You are connected directly to the battery, right?

On 6/2/2010 8:31 AM, Kevin W0KLH wrote:
I just reinstalled my Icom back into my vehicle after it being out for
several months, I was listening to 20 meters yesterday and tried to
get into a few of the pileups that were going on. A second or two in
keying up to ID my call, the radio shuts off. I also have developed
what sounds like a ground hum on VHF.

For an antenna I am using a Yaesu ATAS-100 with a AM-COM controller.
When tuning the antenna in, I get to very low SWR's on the meter, so I
don't think that it is a high SWR that is causing it. I have checked
all connections and they are tight, so any thing further I can check?

Thanks

Kevin
w0klh

Don't know if you have the head remoted or not. If so, the instructions
are very clear about grounding of the plug on the back of the control
head, or something that effect.

Andy W4KDN



--
Two most common elements in the universe- Hydrogen & Stupidity

In article
,
Kevin W0KLH wrote:

A second or two in
keying up to ID my call, the radio shuts off.

Kevin-

I have the same problem with an IC-7000. I first thought there might be
RF getting into the rig causing the problem. I eventually found it is
actually caused by low supply voltage, as others have noted. With the
engine running, it usually works OK, but sometimes there is sufficient
voltage drop in the wiring that it turns off even then.

What I have done is to install an MFJ-4416 Super Battery Booster. It is
a DC-to-DC power inverter that produces a constant 13.8 Volts DC from a
varying input voltage. With that turned on, I've never had the rig turn
itself off. The booster is effectively out of the circuit when it is
turned off, so I leave it off until the problem occurs.

Fred
K4DII