Hey everyone,

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I am new to this group and I am in the process of repairing a few IC-7000s.? One was given to me by my grandfather and the other was my dad's that failed and was deemed irreparable due to parts being unavailable.? Turns out my dad's IC-7000 was actually my grandfather's (KB4NZJ's).? My grandfather passed away a few years ago and his IC-7000 became a donor radio to fix mine, but after finding out the history, I am determined to fix it.? My radio had the dreaded click-click problem no turn on problem.? My grandfather's, wouldn't turn on, I never tried it, but was listed with Bad Main Board, Bad Logic Board, and Bad DDS Module.? My desire to fix it was originally to learn a new skill and do something nice for my dad, but after finding out the story behind the radio, its more sentimental.

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KB4RU (IC-7000 Fix)
My radio was repaired once before but after about a year, it failed again.? I found once I pulled apart the display unit, the Capacitors that were supposed to be 100uf 16v were actually 47uf 25v.? I was afraid this took out parts in my radio and after tearing it apart and checking it over, I found nothing appearing damaged. Pulled apart the other display unit and turns out the screens were switched at some point between the radios.? Put the other screen on mine, and it came back to life.? Thank god, easy fix for the first one.? Replaced the Capacitors with the correct ones and the other display unit now works and turns the radio on.? Looks like one of the 2 caps failed.? FYI, Digikey lists 100uF 20v as an upgrade for the caps, they are slightly too thick and create a bulge in the back of the display case.? Stick to the 16v.

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Onto the second radio. KB4NZJ (Silent Key) IC-7000

Display Board- This is the older IC-7000, the display board above had the 47uf 20v Caps described above.? Replaced caps and its working as it should now.

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Main Board- I thought I had a burned resistor and failed cap near the logic board connection point.? Cleaned the char off and found a burnt trace going to the connector.? I attempted to bridge the trace and the wire kept shifting to the space between the pins. I tried to remove the connector and make a new trace, but everything kept moving around it kept getting worse until I ended accidently pulling up the whole trace.? After several hours trying to make something work, I gave up and ordered a new main board for now.? Eventually, I will try to cut and make a new trace to keep the mainboard as a spare.? Surface mount PCB repairs and overall radio repairs is a new learning experience for me.??

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Logic board- Found a burned inductor on the back side of the logic board.? Replaced the inductor and logic board appears to be working again!? I tested it in my radio and it powered up and appeared to be working normally.

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DDS- Says No RX, No TX.? I have looked all over it with magnifying glass and have not found anything appearing damaged.? I haven't poked around with the multimeter yet, but I decided to start with the Main Board and Logic to see if I can get it to power on, then try the DDS board.? I am not sure how it was tested to determine it was no good.? May have originally come out of my radio, but I am not sure which part came from which radio originally anymore.??

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Inspiration for others.

Hopefully this helps someone else have some hope in restoring their IC-7000 and keeps a few more of these wonderful radios alive.? I will post up some pictures of the projects later on.? I never attempted to repair these myself before because it was outside of my comfort zone and something I never did before.? However, I had the option of try it and see what happens and learn something new or give up on the radio and let it sit in the attic.? Glad I did.? A lot of this is easier than I expected, and I am learning a lot as I go along.? I have minimal experience fixing radios and by no means an expert in soldering or electronics repair.? My dad taught me the basics and I learned the rest on YouTube.? So, don't give up.? If you're determined enough, it can be done.

I have done a little more troubleshooting around the LPF final filter section.? I unplugged the cable from the main board to the PA.? I set the freq to 14.2 MHz.? I separated the output of L305 transformer and injected a 14.2 signal into C327 and looked at ant1 with a scope.? When I pushed tx the signal is seen at a reduced level at ant1.? I also saw the signal reduce at the input when tx is activated.? The signal level was 7 volts and is reduced to 3.5 volts when tx is activated.

I also saw 0 ohm resistance of the tx path of the RL801 at tx.? I also saw 0 ohms resistance inward side of C327 and C972 at tx.

I just chose 14.2 but all the filter paths are similar.

Please provide comments and suggestions.

Thanks

Tommy

On Fri, Jan 31, 2025 at 3:22?AM Andrew Lenton via <a=[email protected]> wrote:

20% high does not sound too bad!!

It is when they drop low and you lose 90% will be the issue.

73

Andrew

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On 30 Jan 2025, 20:28, at 20:28, "Tommy Wooten via " <kf4rwg=[email protected]> wrote:
>JD
>I think Andrew suggested that capacitors may be the issue.? There are
>two
>large smt capacitors in the filter section after the PA section.? I
>removed
>these and measured them.? The result is as follows:
>C327 = 942 nF
>C972 = 811 nF
>
>These are rated at 680 nF and measure 20 to 30% high in value.
>
>I will check other caps in the path before the driver.
>
>Any thoughts?
>
>Tommy
>
>
>
>
>On Wed, Jan 29, 2025 at 1:02?PM J.D. Barron via
><jeter.d.barron=
>[email protected]> wrote:
>
>> RL801 may not be making good contact. You can check the levels with
>your
>> scope. I would use SSB and whistle in the Mike for tracing to keep
>the
>> power dissipation low.
>>
>> On Wed, Jan 29, 2025, 11:51?AM J.D. Barron via
><jeter.d.barron=
>> [email protected]> wrote:
>>
>>> Take a good look at RL801
>>>
>>> On Wed, Jan 29, 2025, 11:06?AM Tommy Wooten via <kf4rwg=
>>> [email protected]> wrote:
>>>
>> JD
>>>>
>>>> I was able to access each of the relay leads from the top side of
>the PA
>>>> board.? I found that each relay had the 14VR supplied at the relay
>coil.
>>>> The voltage is 10.5V and falls to 9.2V when tx is activated.? I
>verified
>>>> that L1 thru L7 leads were 10.5V and dropped to 130mV (gnd) when
>activated
>>>> by the appropriate band selection.? PHT8 at RL801 acted same when
>tx is
>>>> activated.
>>>> All gnd readings were 130mV except RL941 read 363mV as an
>observation.
>>>> All relays seem to click appropriately when each band was selected.
>>>> I cannot access IC981 since it is on the bottom side of PA.? But
>from
>>>> the info above it indicates it is working correctly.
>>>>
>>>> This does not explain why I was able to see 6W at the output of
>L305 but
>>>> I see negligible power when it passes through the filters.? There
>must be a
>>>> short or open in path.
>>>>
>>>> No smoking gun yet!
>>>>
>>>> I won’t stop until I find the issue or tear something up.
>>>>
>>>> Thanks
>>>> Tommy
>>>>
>>>> On Tue, Jan 28, 2025 at 5:45?PM J.D. Barron via
>>>> <jeter.d.barron=[email protected]> wrote:
>>>>
>>>>>
>>>>> (PA 1) The RF comes from L305? through HF03 to RL-801 (PA 2)
>(changes
>>>>> from orange to blue and out through (A). to
>>>>> (PA 3) the bandpass filters. There are a pair of relays that have
>to be
>>>>> energized for each frequency band. The input relays are controlled
>by L1 -
>>>>> L7 (Bus line 3) from the (PA 3) Q980 - Q987 by the outputs from
>IC981.
>>>>> (Powered by 3R3V)
>>>>>
>>>>> 14 VR provides the operating voltage for these relays and the
>output
>>>>> relays. (At this point I have to say I have not looked long enough
>and hard
>>>>> enough to understand how the output relays are activated but they
>must be.)
>>>>> as each band is selected by L1 - L7 going low.
>>>>> VR14 comes from RL701 output through L981 and resistors R1002 (150
>ohm)
>>>>> and 1003 (180 ohm) (paralleled). This line also provides power to
>RL801
>>>>> which would also stop the RF power from getting to the bandpass
>filters
>>>>> HF03 (Orange) to A (Blue). If R1002 and R1003 were open this would
>cause
>>>>> this problem as well. One of the anti-flyback diodes shorted could
>take out
>>>>> these resistors
>>>>>
>>>>> I think that as each L1 - L7 goes low that low is transferred via
>the
>>>>> blue line to the normally closed contact on the relay below to
>ground on
>>>>> the unenergized relay (I think).
>>>>>
>>>>> I would verify that the VR14 voltage is present first and then -
>if
>>>>> present
>>>>>
>>>>> I would look for the L1 - L7 signals being pulled low by Q980 -
>Q987.
>>>>> end then If switching I would look to
>>>>> The outputs on IC981.
>>>>>
>>>>> I believe you will find the problem in this area as you are
>drawing
>>>>> current indicating power being produced (unless the current is not
>in the
>>>>> 1-3 Amp range in SSB no modulation idling current).
>>>>>
>>>>> Since the power is not going through L961 the FOR / REV (SWR)
>>>>> transformer and being read by IC060 (JFOR) the RF drive is going
>to the
>>>>> point of current limit and cannot be adjusted in any carrier mode
>with the
>>>>> power adjustment.
>>>>>
>>>>> Just my best guess without making some measurements, but this is
>where
>>>>> I would start.
>>>>>
>>>>> Good luck and best regards.
>>>>>
>>>>>? JD
>>>>> KE4MD
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>
>>
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