Call Search

New to Ham Radio?
My Profile

Friends Remembered
Survey Question

DX Cluster Spots

Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement

donate to eham
   Home   Help Search  
Pages: [1]   Go Down
Author Topic: My Icom 7000 is back, an update  (Read 1620 times)

Posts: 263


« on: September 10, 2006, 02:12:48 PM »

I finally got back my 7000 from Icom.

Actually they gave me a new one.  So no more problems.

I had actually bought a second one to use on a DXpedition and also replace the big clunky 746 in my shack.  That one was working in the car for the time being.

I don't think heat was ever a problem with my 7000 in the car.  I just drove 100+ miles round trip and was working the WAE contest from the car and when I got out of the car back at home the radio was cool as a cucumber.  I mean, not Icom hot, but really really cool.

Maybe I just had bad luck.  Or maybe something else was wrong with that other 7000 that Icom is yet to figure out.

For power protection I have a relay installed in series plus the W4RRY battery booster and the surge suppressor recommended by AD5X.  So I should have zero power problems now, if I ever had any to begin with.  

Oh well...

Posts: 10248


« Reply #1 on: September 10, 2006, 04:44:46 PM »

I have two as well, and both work well. The newest one, I disassembled into about 50 pieces, and managed to get it back together, and you'd never know it was apart.

I recently purchased a Service Manual, and I recommend it for any serious amateur. After taking one apart, looking over the circuitry, operating one mobile for nearly 5,000 miles, I have a few insights.

If you use proper wiring techniques, and you don't over-drive the radio, and you are in motion (engine running), you don't need any voltage compensation (i.e.: W4RRY booster) to achieve a clean output. Using one doesn't hurt, but is is a waste of resources.

The same goes for filtering too. I am aware that the European versions have an requisite filter for DC operation, but I don't believe it is at all necessary for clean operation. If you take time to look at the schematic of this filter, you know why it (and others) is superfluous.

I never switched the DC power from my 7000, or any other radio I have EVER used mobile (solid state or tube). I can't remember any problem that is caused, or might have caused. In fact, switching power on and off most likely would cause more problems, not less (spikes etc.).

There are those that feel automotive starting motors cause enough impressed spikes to elicit all sorts of failures including those in the final circuitry. If this were the case, you be reading about it all over the net. You don't.

The areas of mobile operation which need special attention are proper antenna mounting and feeding; adequate wiring and fusing; all manner of bonding; and in about that order.

Alan, KØBG


Posts: 263


« Reply #2 on: September 10, 2006, 04:56:34 PM »

I have bad news.

But first of all, let me say why I have the W4RRY booster.

Often I would go somewhere and operate portable.  I prefer not to pollute the air any more than I have to so I turn the engine off.  Of course with less than 13.8 volts the radio outputs less than full power.  

Secondly, I notice the car's electrical system sometimes will shift to 12.5 volts instead of 13.8.  I was told this is a normal, Honda thing to save gas.  If you turn on a heavy load (headlights or A/C) the voltage will bump back up to 13.8.  But intermittent SSB won't cause it to go back up.  

Anyway the bad news.

I was using the new 7000 back from Icom IN THE SHACK (not in the car) for the WAE contest with a 20m dipole outside. I use an LDG AT-7000 for protection.  The dipole doesn't have any high SWR.  

But 20 minutes ago, all of a sudden, without me transmitting, POP and it let out its magic smoke.

No transmit.  Finals dead again.

How on earth did this happen?

Totally new radio, different antenna, not even in the car.  I'm using a 28A regulated switching power supply which is rock solid and so stable I never see the voltage vary from 13.77.   I figure I must be cursed or something.

I wonder if Icom will repair it this time again?  They will certainly think it is my fault.

The second 7000 in the car is tooling along just fine. Almost two weeks and not a peep!  

Posts: 14496

« Reply #3 on: September 11, 2006, 07:13:54 PM »

I'd suspect the power supply if you had two radios fail using it and they worked fine in the mobile. It could be putting out a spike that doesn't show up on the voltmeter.

Bob  AA4PB
Garrisonville, VA

Posts: 175

« Reply #4 on: September 23, 2006, 01:00:48 AM »

Is it possible that something in your transmission line or antenna and/or mount is shorting out?  I had a problem about 15 years ago with a well used connector shorting out and now I clip and install fresh coax connectors every year or so (or earlier if I think necessary).
Pages: [1]   Go Up
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!