On Jun 18, 2023, at 8:41 AM, N3EA <amaslin@...> wrote:

Hi..my IC-7000 has been showing low power output for a while now. This is on the Po meter on the rig. The maximum reading has been showing around 80 watts when connected to my mobile antenna. The rig is used mobile all the time.? I put the rig on a dummy load and compared it to another IC-7000 that my son brought over for this test. His rig shows slightly over 100 watts output when the radio is set to RTTY on 20 meters and output at 100%. The Po meter also shows 100% power. The output varies a little from band to band but that's not really the issue. When my '7000 is set to the same frequency as his, same mode, same load, same power supply, my radio is also showing slightly over 100 watts output at the load. However, on my radio the power Po meter on the front panel is only showing around 80 watts output. Is there a way to adjust the power out meter on the radio or is there a known problem like this with some '7000's? This problem exists on both HF and VHF/UHF.? Any ideas out there???
Thanks & 73,

Al, N3EA

Hi..my IC-7000 has been showing low power output for a while now. This is on the Po meter on the rig. The maximum reading has been showing around 80 watts when connected to my mobile antenna. The rig is used mobile all the time.? I put the rig on a dummy load and compared it to another IC-7000 that my son brought over for this test. His rig shows slightly over 100 watts output when the radio is set to RTTY on 20 meters and output at 100%. The Po meter also shows 100% power. The output varies a little from band to band but that's not really the issue. When my '7000 is set to the same frequency as his, same mode, same load, same power supply, my radio is also showing slightly over 100 watts output at the load. However, on my radio the power Po meter on the front panel is only showing around 80 watts output. Is there a way to adjust the power out meter on the radio or is there a known problem like this with some '7000's? This problem exists on both HF and VHF/UHF.? Any ideas out there???
Thanks & 73,

Al, N3EA

This is a common problem with the IC-7000 since it is very sensitive to low voltage. The OEM power cables with glass fuses are terrible. Over time the brass fuse clips form an oxide layer that quickly builds high resistance. Not good for the high current demand of a 100 watt HF rig.? Check for voltage drop across the fuses. A two volt drop at 15 amps is a 30 watt input loss equating to roughly a 15 watt output power loss. When I get a new radio I replace the plastic fuse holders with good quality ATC blade fuse holders. Also, as part of my radio preventative maintenance routine I? reseat fuses to try and avoid the problem.

Steve
73 de KC4SM

Jun 18, 2023 8:42:07 AM N3EA <amaslin@...>:

Hi..my IC-7000 has been showing low power output for a while now. This is on the Po meter on the rig. The maximum reading has been showing around 80 watts when connected to my mobile antenna. The rig is used mobile all the time.? I put the rig on a dummy load and compared it to another IC-7000 that my son brought over for this test. His rig shows slightly over 100 watts output when the radio is set to RTTY on 20 meters and output at 100%. The Po meter also shows 100% power. The output varies a little from band to band but that's not really the issue. When my '7000 is set to the same frequency as his, same mode, same load, same power supply, my radio is also showing slightly over 100 watts output at the load. However, on my radio the power Po meter on the front panel is only showing around 80 watts output. Is there a way to adjust the power out meter on the radio or is there a known problem like this with some '7000's? This problem exists on both HF and VHF/UHF.? Any ideas out there???
Thanks & 73,

Al, N3EA

I think he may be asking is there a way to calibrate the Po meter with what is actually measured at the antenna jack. His is indicating 80 watts but is actually measuring 100 watts at the antenna jack.

There might be something in the service menu but someone else would have to chime in on how to access it & which setting to change.

73
John Denison
KD5YOU

On 6/18/2023 5:27 PM, Steve Murphy wrote:

This is a common problem with the IC-7000 since it is very sensitive to low voltage. The OEM power cables with glass fuses are terrible. Over time the brass fuse clips form an oxide layer that quickly builds high resistance. Not good for the high current demand of a 100 watt HF rig.? Check for voltage drop across the fuses. A two volt drop at 15 amps is a 30 watt input loss equating to roughly a 15 watt output power loss. When I get a new radio I replace the plastic fuse holders with good quality ATC blade fuse holders. Also, as part of my radio preventative maintenance routine I? reseat fuses to try and avoid the problem.

Steve
73 de KC4SM

Jun 18, 2023 8:42:07 AM N3EA <amaslin@...>:

Hi..my IC-7000 has been showing low power output for a while now. This is on the Po meter on the rig. The maximum reading has been showing around 80 watts when connected to my mobile antenna. The rig is used mobile all the time.? I put the rig on a dummy load and compared it to another IC-7000 that my son brought over for this test. His rig shows slightly over 100 watts output when the radio is set to RTTY on 20 meters and output at 100%. The Po meter also shows 100% power. The output varies a little from band to band but that's not really the issue. When my '7000 is set to the same frequency as his, same mode, same load, same power supply, my radio is also showing slightly over 100 watts output at the load. However, on my radio the power Po meter on the front panel is only showing around 80 watts output. Is there a way to adjust the power out meter on the radio or is there a known problem like this with some '7000's? This problem exists on both HF and VHF/UHF.? Any ideas out there???
Thanks & 73,

Al, N3EA

Steve,

That's right. That's what has me confused. The measured output is 100 watts into a dummy load but the meter on the rig says it's 80 watts. I appreciate the suggestions about the fuse issue, and I may just put new ones in anyway, but I just didn't get how the DC voltage being a bit low could affect the meter reading and not the actual output. I might also add that no one, including me, has ever been inside of this '7000 so whatever is going on is probably due to the radio being older. I don't have the service manual here but I thought that there might be some way to calibrate the meter or at least see what component(s) might need to be replaced.

Thanks,

Al, N3EA

John,

He did say his radio also produced 100 watts at the load. I've seen the ic-7000 low voltage, reset, power out issue so many times that I went right to the fuse problem.
73

Jun 19, 2023 5:38:29 PM John Denison <kd5you@...>:

I think he may be asking is there a way to calibrate the Po meter with what is actually measured at the antenna jack. His is indicating 80 watts but is actually measuring 100 watts at the antenna jack.

There might be something in the service menu but someone else would have to chime in on how to access it & which setting to change.

73
John Denison
KD5YOU

On 6/18/2023 5:27 PM, Steve Murphy wrote:

This is a common problem with the IC-7000 since it is very sensitive to low voltage. The OEM power cables with glass fuses are terrible. Over time the brass fuse clips form an oxide layer that quickly builds high resistance. Not good for the high current demand of a 100 watt HF rig.? Check for voltage drop across the fuses. A two volt drop at 15 amps is a 30 watt input loss equating to roughly a 15 watt output power loss. When I get a new radio I replace the plastic fuse holders with good quality ATC blade fuse holders. Also, as part of my radio preventative maintenance routine I? reseat fuses to try and avoid the problem.

Steve
73 de KC4SM

Jun 18, 2023 8:42:07 AM N3EA <amaslin@...>:

Hi..my IC-7000 has been showing low power output for a while now. This is on the Po meter on the rig. The maximum reading has been showing around 80 watts when connected to my mobile antenna. The rig is used mobile all the time.? I put the rig on a dummy load and compared it to another IC-7000 that my son brought over for this test. His rig shows slightly over 100 watts output when the radio is set to RTTY on 20 meters and output at 100%. The Po meter also shows 100% power. The output varies a little from band to band but that's not really the issue. When my '7000 is set to the same frequency as his, same mode, same load, same power supply, my radio is also showing slightly over 100 watts output at the load. However, on my radio the power Po meter on the front panel is only showing around 80 watts output. Is there a way to adjust the power out meter on the radio or is there a known problem like this with some '7000's? This problem exists on both HF and VHF/UHF.? Any ideas out there???
Thanks & 73,

Al, N3EA

Hi Al,

From memory, I don't believe there is an adjustment in the service menu for the output power meter. RF power is sampled from the PA unit, one for vhf/uhf the other for HF. The two lines are combined into a single line and passed to the main board via a ribbon cable connection. The signal then goes to an analog input on the main CPU. There are no trim pots in the signal paths that can be adjusted.
Since your 7000 has been used in a mobile environment a good place to start might be? connections. There is a ribbon cable between the PA and the Main board that carries the sampled RF power. If you are comfortable attempting some troubleshooting you might try reseating or carefully and gently disturbing the ribbon cable at the connectors using an orange stick or similar non-conductive tool. Be careful as the ribbon cables are delicate and are prone to failure. If you accidentally unseat the ribbons that come from the lower side of the chassis they can be very difficult to reconnect. If I were troubleshooting I would gently push and pull on the ribbon while transmitting and see if the power indication changes. If it does then possibly reseating the ribbon cable could resolve your issue.

I hope you are able to fix it. The 7000 is a great radio. I wish ICOM still serviced them. At least you know you are getting full power out of the radio but I too would be annoyed if the power meter wasn't indicating correctly.

Steve
KC4SM

Jun 20, 2023 9:31:56 AM N3EA <amaslin@...>:

Steve,

That's right. That's what has me confused. The measured output is 100 watts into a dummy load but the meter on the rig says it's 80 watts. I appreciate the suggestions about the fuse issue, and I may just put new ones in anyway, but I just didn't get how the DC voltage being a bit low could affect the meter reading and not the actual output. I might also add that no one, including me, has ever been inside of this '7000 so whatever is going on is probably due to the radio being older. I don't have the service manual here but I thought that there might be some way to calibrate the meter or at least see what component(s) might need to be replaced.

Thanks,

Al, N3EA

I believe that the Power Output meter calibration is set when doing the TX Output Power adjustments for the HF, 6M, VHF and UHF bands at the Min, 25%, 50% and 100% power levels.? This sets the ALC reference voltage level to control the output power and also the analog to digital translation of the forward power detector voltages used to display the Po meter reading.

It is important to follow the adjustment procedures closely and have accurate test equipment.? For the TX Output Power adjustments for example, it is important to drive the mic audio with a 30 mv. audio signal.

Trimmer pots have been replaced by digitally programmed A/D amd D/A logic for decades now in most designs.??

Steve, W3AHL

?

A bit more info.

After looking at the readings into the dummy load while the radio was mounted in the car, I then took it into the shack and powered it up using my SEC-1223 power supply. The results were the same. So, since I was using a different power source, a different cable (no blade fuses) but the same load, I'm assuming that the radio has a problem. It might also be interesting to note that the power output readings at the rig on VHF and UHF are also showing low plus when changing HF bands the error is still the same no matter which band I tried.?

I no longer have much test gear here as I just don't have the room for a work bench at the new QTH. I will probably have to contact Icom to see if they still service the '7000 radios.?

Thanks to everyone for their comments. I have learned a lot from you all.

73,

Al, N3EA

?

A bit more info.

After looking at the readings into the dummy load while the radio was mounted in the car, I then took it into the shack and powered it up using my SEC-1223 power supply. The results were the same. So, since I was using a different power source, a different cable (no blade fuses) but the same load, I'm assuming that the radio has a problem. It might also be interesting to note that the power output readings at the rig on VHF and UHF are also showing low plus when changing HF bands the error is still the same no matter which band I tried.?

I no longer have much test gear here as I just don't have the room for a work bench at the new QTH. I will probably have to contact Icom to see if they still service the '7000 radios.?

Thanks to everyone for their comments. I have learned a lot from you all.

73,

Al, N3EA