low power out on HF
Jamie WW3S <ww3s@...>
Only getting about 25 watts out or so on HF, VHF/UHF is fine, full power.....Its NOT the power cord, I've tried a couple different ones, same result, and those cords work fine with my 7300, I had a problem with the 7000 before, actually no power out on HF and SARS in Michigan, replaced maybe the driver transistor, is it common for this part to go bad? Any thing to watch out for to prevent it from happening in the future.
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Ludovic Ludo
replaced maybe the driver transistor, is it common for this part to go bad ? This is not the driver in question, it is common to HF and V / UHF. To prevent this failure, do not use more than 30W in FM or numerical mode (FT8, etc) like all the 100W tranceivers. Best regards, Ludovic - F5PBG. http://radioamateur.forumsactifs.com/f36-ic-7000
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Helmut Wabnig
On Tue, 19 Jan 2021 08:34:23 +0100, you wrote:
With the appropriate care, the 7000 is capable of working 100% power,replaced maybe the driver transistor, is it common for this part toThis is not the driver in question, it is common to HF and V / UHF. that is, 100 watts on HF , 50 w on VHF and 30 w on UHF, in FT8 with its (the FT8) 50% duty cycle. All those "don'ts" and "do nots" are based on unsufficient technical knowledge. As for the original poster's complaint, his 7000 does not deliver the rated capacity power, yes, there is perhaps a hardware problem and you will possibly have to replace the driver and/or the finals. I cannot remotely diagnose the fault. Must have my hands on :-) Sorry for being nasty, but those "don't do this" pull my nerves. OE8UWW
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The IC7000 is known to develop issues with the driver and the finals also. Even in this group there are several posts about this topic. Otherwise Google is your friend.
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Paul Hansen
25 watts kind of indicates one of the PA transistors has failed. Measure the gate voltage in TX. It should be anywhere between 3.5 and 4.5 volts. It should also be zero in RX.
Thank You
Paul W. Hansen, W6XA Amateur Radio Service 2134 Carthage Road Tucker, GA 30084 (864) 222-3539 www.amateurradioservice.com
From: ic7000@groups.io
[mailto:ic7000@groups.io] On Behalf Of Jamie WW3S
Sent: Monday, January 18, 2021 21:49 To: ic7000@groups.io Subject: [ic7000] low power out on HF
Only getting about 25 watts out or so on HF, VHF/UHF is fine, full power.....Its NOT the power cord, I've tried a couple different ones, same result, and those cords work fine with my 7300, I had a problem with the 7000 before, actually no power out on HF and SARS in Michigan, replaced maybe the driver transistor, is it common for this part to go bad? Any thing to watch out for to prevent it from happening in the future.
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Mark Langenfeld
Very first thing: check the fuses in the DC supply cable for oxidation. They are notorious for that and, when contaminated, cause a significant voltage drop that can manifest as a loss of TX power out. This may or may not be your problem, but it is a simple check that could (if the culprit is found there) save you headaches and money. GL es 73, Mark -- WA9ETW
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Jamie WW3S <ww3s@...>
On TX, I get almost 7 volts on 1 final.....less than half a volt on the other.....looks like that area got very hot at one time....should there be heat sink compound between the metal plate on top of the finals and the case? The VHF/UHF finals all have "springs" on them to contact the case, not so on the hf finals ?
------ Original Message ------
From: "Paul Hansen" <pwhansen@...>
To: ic7000@groups.io
Sent: 1/19/2021 8:26:21 AM
Subject: Re: [ic7000] low power out on HF
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igor-m <mikki@...>
Jamie, download the Service manual, cut off the part of the schematics of the finals from it, and put your measured values at the wires around the transistors. Show the part of the schematics then. People from electronics communicate via schematics - they may help you when they see the values at the specific nodes...
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Paul Hansen
Those are metal shields and there isn’t any heat sink compound on them. The compound is on the bottom of the transistors. 7 volts is way too high and nearly zero is way too low. Sounds like both of them are shot. Base on the amount of damage you are seeing, make sure the current sensing resistors are good. Usually, a visual inspection is all you need. Don’t forget to set the bias on each transistor when you replace them.
Thank You
Paul W. Hansen, W6XA Amateur Radio Service 2134 Carthage Road Tucker, GA 30084 (864) 222-3539 www.amateurradioservice.com
From: ic7000@groups.io
[mailto:ic7000@groups.io] On Behalf Of Jamie WW3S
Sent: Tuesday, January 19, 2021 13:14 To: ic7000@groups.io Subject: Re: [ic7000] low power out on HF
On TX, I get almost 7 volts on 1 final.....less than half a volt on the other.....looks like that area got very hot at one time....should there be heat sink compound between the metal plate on top of the finals and the case? The VHF/UHF finals all have "springs" on them to contact the case, not so on the hf finals ?
------ Original Message ------ From: "Paul Hansen" <pwhansen@...> To: ic7000@groups.io Sent: 1/19/2021 8:26:21 AM Subject: Re: [ic7000] low power out on HF
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Jamie WW3S <ww3s@...>
well, got the final verdict on my 7000.....Matt from SAR in Michigan called today, turns out it was NOT the finals NOR the driver board.....apparently a diode that biases the finals went bad, Matt said he never saw that one before.....again, very prompt and courteous service from Matt in SAR Technical in Michigan, he just received my radio Friday, and called me about 10 am this morning !!!!
------ Original Message ------
From: "Paul Hansen" <pwhansen@...>
To: ic7000@groups.io
Sent: 1/20/2021 6:38:08 AM
Subject: Re: [ic7000] low power out on HF
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wa5itw
I have personally experienced this, after discovering 30 watts output on hf on a used rig I bought. I was not happy, but amazed to discover warmth around the fuse holders and adjacent power cable. I measured around 1.4 or more volts drop at radio thanks to this oxidation that I discovered on the fuse blades. I cleaned them back to shiny state, and problem was resolved for only a while...so I soldered the fuses inside the fuse cases and no problems since- full power out, no more excessive voltage drop (the IC 7000 requires near full voltage for expected power out). I was amazed. The two lines of oxidation were very visible on the fuse blades before buffing them out. 73, Steve W5ZA
On Tue, Jan 19, 2021 at 10:58 AM Mark Langenfeld <lmlangenfeld@...> wrote:
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Helmut Wabnig
On Tue, 30 Mar 2021 14:34:17 -0500, you wrote:
I have personally experienced this, after discovering 30 watts output on hf Usually only one fuse is sufficient, remove the ground wire fuse. w
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D C *Mac* Macdonald
Do NOT, repeat, do NOT remove the ground leg fuse
in a mobile installation. A lost vehicle ground can
cause attempting to start the vehicle to use your
expensive radio to become the ground path according
to many sources. That is why the factory lead has
that fuse.
73 - Mac, K2GKK/5
Since 30 Nov 1953
Oklahoma City, OK
USAF (Retired) 61-81
FAA (Retired) 94-10
From: ic7000@groups.io <ic7000@groups.io> on behalf of Helmut Wabnig <hwabnig@...>
Sent: Wednesday, March 31, 2021 02:16 To: ic7000@groups.io <ic7000@groups.io> Subject: Re: [ic7000] low power out on HF On Tue, 30 Mar 2021 14:34:17 -0500, you wrote:
>I have personally experienced this, after discovering 30 watts output on hf >on a used rig >I bought. I was not happy, but amazed to discover warmth around the fuse >holders and >adjacent power cable. I measured around 1.4 or more volts drop at radio >thanks to this >oxidation that I discovered on the fuse blades. I cleaned them back to >shiny state, and >problem was resolved for only a while...so I soldered the fuses inside the >fuse cases and no >problems since- full power out, no more excessive voltage drop (the IC 7000 >requires >near full voltage for expected power out). > >I was amazed. The two lines of oxidation were very visible on the fuse >blades before >buffing them out. > >73, > >Steve W5ZA > Usually only one fuse is sufficient, remove the ground wire fuse.
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Not so fast! It is prudent to fuse both sides of the power cord. Just make sure the contact points are clean. Use a Dremel wire brush and then apply some DeOxit to retard future oxidation.
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73, Michael, W1RC
On Mar 31, 2021, at 3:16 AM, Helmut Wabnig <hwabnig@aon.at> wrote:
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Mark Brueggemann
On Wednesday, March 31, 2021, 05:30:24 AM MDT, D C *Mac* Macdonald <k2gkk@hotmail.com> wrote:
your expensive radio to become the ground pathPossible only if you connect your radio negative lead to the battery negative terminal, which is bad installation practice. Which I guess is one reason to keep the fuse, to protect people from themselves... Mark K5LXP Albuquerque, NM
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Kurt Sweeny
Has anyone found a good replacement for the stock fuse holders? I am thinking of replacing the stock holders but would like to avoid a weak/ ugly wire to wire splice.
toggle quoted messageShow quoted text
Kurt KD6LZV ———————-
On Mar 31, 2021, at 8:10 AM, Mark Brueggemann via groups.io <qrq_cw=yahoo.com@groups.io> wrote:
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