Date   

Re: Who wants to compare PCB'S

 

Short answer Paul, Don't use 73 when you don;t mean it and don't expect anyone to help when you go out of your way to be rude.
I am sorry I tried to help you, but it won't happen again.

AR


Re: Who wants to compare PCB'S

 

If you look at the manual PCB layouts for the versions you are interested in you can tell more than the pictures will tell you. The schematic is fairly clear and the pictures of both sides would be informative. 
If you will only be satisfied with pictures and choose to degenerate those who are trying to help you then you are on your own.
I have spent a good bit of time working on these radios and it takes a really good magnifying glass and light and sometimes a USB "microscope" camera  attached to said magnifying glass. 
I can assure you that it is far easier to understand the circuit from the schematic if you understand these things and there is a great deal that is difficult enough to figure out even on the schematic and tracing the circuit visually without reference to the board layouts would be impossible for me, but with your supreme abilities I guess you can see through the components and on both sides of the board with a good picture to blow up.
Now you are on your own as far as I am concerned.


Re: Who wants to compare PCB'S

Steve W3AHL
 

Google for: icom ic-7000 service manual addendum   It's availailable in mods.dk.   It is 307 pages and consists of the original 2005 service manual and then four updates for 2008, 2009 and 2010.  I know changes were made after 2010, but am not aware of publicly available iniformation on them, other than the 60M band change TSB in 2012.  I have never checked if all PCB artwork revisions are covered and I don't have a complete list from the radios I've worked on anyway.

I agree with J.D.'s response.  Pictures provide no understanding of the changes you might see in the photo's.  And some of the important changes are in the PCB artwork that improve grounding, reroute signals to reduce coupling, etc.  Many changes aren't functional, but were needed to source alternate parts when the orignal components were end of lifed.  Some changes in schematics and block diagrams simply corrected errors in the document, not changed the design.

If you are hoping to find changes that will fix a specific problem you believe exists in your radio, don't get you hopes up.  Some problems are in the firmware, which Icom hasn't changed and can't be field updated anyway.

Steve, W3AHL


Re: Who wants to compare PCB'S

 

I have looked at the boards and without a very good magnifying glass you might have a problem.
Compare the schematics and then look to see what is different. What is on the schematic is more important.
If your concern is the driver board the manual has a very good drawing of the two boards and you could tell the difference more easily along with comparing the schematic to see if there is an electrical difference and a mechanical difference. 
I have replaced a few driver transistors and I think that they have all been in later units. At least one blew out when I accidentally pushed the tune button and the tuner started switching, but unfortunately there was no antenna attached (my mistake). A pop and the magic smoke escaped.

On Sat, Jun 13, 2020 at 12:36 AM Paul <pg321@...> wrote:
Service Manual combined updates ? never heard of it or seen it , got a link .

I'll disagree on the pictures though , i'm good at looking at what has changed in the relevant areas , self explanatory imo .

73



--
J.D. Barron


Re: Who wants to compare PCB'S

Steve W3AHL
 

Or you can download the Service Manual combined updates and look at the PCB artwork, parts list and schematics.   Photos won't show you much.

Steve, W3AHL


NEW! CT-17B-6BT Bluetooth 6 ports CI-V hub.

VE2DX
 

Hey Gang, here is anothor of my TERRIBLE quality videos of a Bluetooth 6 port CI-V hub.

The CT-17B-6BT (Name change from the unit in the video CT-17B-5B) has 5 RF filtered CI-V ports and a Bluetooth interface for a serial port to your PC application.

https://www.youtube.com/watch?v=omobEDdySQI

The unit is powered by any regular Micro-USB power supply and the USB power is also RF Filtered.

Finaly it is enclosed in a 3D printed custom enclosure with magnets to help with the unit installation.

It should be available by july 2020, more info on www.VE2DX.com.

--
73
 
Richard VE2DX, Jesus Island, PQ-014

VE2DX ELECTRONIC 
WWW.VE2DX.COM
Only the Best ICOM, ERC and HRD 
https://groups.io/g/CIV
Follow my projects on www.facebook.com/VE2DX/
 


Re: SWR Spike on 6m

Philippe PARIS
 

Hi Adrian,

I don't test if there are RF spikes on 50 MHz, anyway, i can show you there are huge ones on UHF...

CLICK THERE

Then an IC-7000 in front of an UHF PA could cause some problems.

For information, no spikes on UHF on an FTM-400...

CLICK THERE

If i have some time one day, i will check the IC-7000 on HF, 50 and 144 MHz, just to know how it is ?

73 to all.

Philippe


Re: So what is the Consensus

g4abx
 

All interesting stuff Steve and thanks to this group:

My 7000 is mainly used in the shack -- and because it used to run so warm I installed another little fan resting on top forcing air into the existing fan aperture -- and powered by the antenna plug on the back. It cost all of $3 and has zero impact on the fabric of the rig. No internal mods no resistors no nothing. It just sits there quietly doing its 'thing' and even on digital modes the rig never gets out of the 'green' (I only run 50 watts max)

Its great to have a resource like this. 
Many thanks

73
Bruce G4ABX


Re: So what is the Consensus

Steve W3AHL
 

The problem isn't that the SWR changes during tuning are reflected back to the driver,  but how the SWR affects the ALC loop.  Here are some of the contributing factors, but not all apply to all stations obviously.
  1. Many hams don't understand how autotuners work, their limitations and what loads their antennas present to the autotuner.  This result in abuse of the tuner circuits and the radio.  If you open an autotuner and see inductors that have turned brown due to overheating or capacitors that are darkened or have signs of arcing across the PCB due to excessive voltage, the tuner is being misused.  Harder to see are signs of excessive arcing on the relay contacts that contribute to excessive RF spikes during tuning cycles.  
  2. All of the above indicate that the RF signal being presented to the radio is possibly causing damage.  Maybe not immediate failure, but often latent defects in components that eventually fail for no apparent reason at that time.
  3. Many hams use tuners that do not ensure the radio TX power is reduced to 10 watts during tuning.  There were many tuning interfaces (especially for mobile antennas, which are a challenge to tune due to low impedance and narrow bandwidth) that applied incorrect voltages to the tuner interface, which affected temperature control circuits at the CPU by increasing the reference voltage above 3.3 VDC.
  4. Both the PA and Driver MOSFETs are designed to foldback their power output as the SWR they see increases, up to 20:1.  This power foldback of course signals the ALC to increase IF gain, which can result in big problems during autotuning when relay contacts are often bouncing 2-4 times and then dramatically changing the load on the next tuning cycle.  The ALC becomes erratic (this isn't just a problem with the 7K), power bounces around and the tuner circuit has trouble arriving at a good tuning solution sometimes.  So the operator tries again!
  5. Autotuners usually have memory of prior successful LC solutions for given frequency bands, but many hams use multiple antennas for the same band, with a switch ahead of the tuner.  So switching from a High-Z end fed to a Low-Z vertical for a memorized frequency will select the worst possible LC combination, then do a complete rescan.  Often both antennas present a reactive impedance well outside the rated ability of the tuner, but it can still be tuned to a usable SWR.  But the excessive current or voltage takes its toll on the tuner and eventually the radio.
  6. The Driver tends to be the weaker link in the TX chain because it covers the entire HF-UHF range and operates in class A mode, which is less efficient, but lower distortion.  It also seems to be more sensitive to misadjustment or drift of driver gain per band and other TX adjustments.  I have not been able to observe any specific problems with driver signals during tuning cycles, but it is hard to look at lower level signals adjacent to 100-watt PA circuits.  You have to use a scope probe that eliminates the ground lead and uses a spring ground probe that attaches to the grounding collar right at the tip of the probe.  But that only works if the appropriate ground for the signal being observed is within a few tenths of an inch of the circuit access point.  I can see the ALC overshoot effects mentioned in a previous post, but I didn't see the driver levels approach max spec levels.  But I wasn't testing under worst case scenarios, since I didn't want to destroy my radio....
  7. I have not looked at the very early radios, so they may have had problems I'm not aware of.  My oldest 7K was purchased 11/2006.  I have attempted to repair one of the very early radios, but the least of its problems were driver failures.  That was the radio that made me decide to stop repairing 7K's for others!
  8. My experience over the past 14 years leads me to believe that at least half of most radio failures are due to poor installation and operator error / lack of knowledge.  Many hams have no idea of the basics of antennas, connectors, grounding , antenna choice, etc.  
Steve, W3AHL


Re: So what is the Consensus

Steve W3AHL
 

Below is a repost of my notes from 2013 on driver failures.   I tried to gather more info from users that reported problems, but didn't get much useful detail.  There seemed to be some connection to running to low TX power, antenna tuners into non-resonant antennas and questionable station grounding.

I have also noticed subtle changes in the pre-driver board layout and design as the Main PCB artwork changed.  That circuit has always appeared somewhat unstable to me when trying trouble shoot it.  I don't know if later rev Main board actually improved the pre-driver stability issues I observed.

I have two 7K's (circa 2006 and 2010) and have never had a driver failure.  I have replaced several drivers for local hams over the years, but couldn't find a likely cause of the failure.  Some had no/poor station grounding and I'm not aware of repeat failures after that was fixed, but I haven't stayed in touch with many of them either.
------------------------------------------------------
2013 Notes:

There have been several theories on why the driver board fails along with suggested "fixes", but none seemed based on sound technical analysis, in my opinion.  Here are my rambling thoughts on what I think I know about the situation, with no solid conclusions at the end, unfortunately....

 

The board you replaced is the Driver.  The pre-driver FET's are on the PA board and boost the IF output enough to drive the Driver FET.

 

Others have reported failures while running at lower power levels.  This would seem to suggest a problem with the ALC loop perhaps.  Several radios have a problem with the ALC control delay allowing full power for a few milliseconds before ALC reduces the gain of the IF stages.  This is especially a problem when driving an amplifier.  I haven't seen evidence of this in the 7K, except when compression is on perhaps. 

 

The gain is constant in the pre-driver, driver and PA circuits, regardless of the TX PO.  Power control is accomplished by the ALC signal changing the bias of the IF stages that supply the drive. 

 

Whenever the Driver board or associated circuits on its input or output, you should perform the relevant TX Adjustments per the Service Manual.  See Section 4-4 Drive/Final Idling Current.

 

The Driver runs as a class A amp and setting its idle current (as above) is essential for proper linearity AND to ensure it doesn't dissipate excessive heat.   

 

I suspect there is some truth in owners saying that poor grounding contributes to the problem, especially when there is a high SWR being tuned with an autotuner that is rapidly switching the L-C networks trying to find a match.  The early stages of tuning where the L-C matching may actually increase the mismatch can generate some pretty high voltages when the reactance is much higher than 50 ohms.

 

I only run resonant antennas and only use a tuner for portable operation -- and never have had a driver failure on either 7K after almost 7 years on one and 3 years on the other.  In my opinion, a G5RV is a poor antenna technically.  Yes, you can make contacts on it and just about anything else you string up in the air, but it can be more than a little unpredictable the way most hams have them installed.

 

I have tried looking for a weakness in the Driver chain several times and didn't find anything suspicious.  But I didn't try to destroy my radio with high SWR and an autotuner.  The ALC circuit does encompass multiple control inputs and the loop goes from the SWR detector near the antenna connector, back to the IF stages on the Main board.  So poor grounding of the system (radio, tuner, lightning suppressor, and any equipment connected to the radio) is easier to fix than to figure out how or why it causes the problems. 

 

Also critical is good grounding of the circuit board to the chassis via TIGHT mounting screws and to the outer case via the ground springs.  It is easy for the ground springs to get mashed in and not contact the case adequately.

 

Another area to look at is excessive RF getting into your digital audio input, resulting in power spikes before the ALC can reduce the IF gain.  The best cure for this is proper system grounding, but more importantly, minimizing RFI in the shack by using resonant, matched antennas with effective common-mode chokes at the feed point.  Also, routing low-level signal cables away from RF and power cables and never in parallel.  Use of proper ferrite chokes on the audio cables helps.

 

The best resource for analyzing these issues is at:

 

http://www.audiosystemsgroup.com/K9YC/K9YC.htm

 

Read and reread the first document listed:  " A Ham's Guide to RFI...

 

There was a subtle change in the Driver board in 2010 that removed a 10pf cap to ground on the FET's output.  And there is now an OPTIONAL R103 (100 ohm)in series with the Driver FET's gate input, but the parts list says it is only for EUR, FRA and ESP country code models. Neither of my radios has either change installed.

 

I don't believe the driver is likely to fail due to ventilation problems in normal installations.  90% of the heat is dissipated into the chassis heat sink.  Some owners have reported inadequate thermal compound on that interface, but I have not seen that in the 4-5 radios that I've looked at.  The driver FET isn't being pushed hard at all, thermally.  I do replace the white thermal compound with a very thin film of Arctic Silver compound if I have the Driver board removed.  And I make sure the thermal spread, FET and chassis make "perfect" contact before screwing them back together.

 

It will probably be several months before I have time to revisit possible causes of Driver flame outs.  I'm sure many others will add their experience and opinion with Driver failures.  Unfortunately, I feel many of these problems are often related to the individual's unique installation of everything that makes up the radio system.  Which is why there are some many different experiences and conclusions drawn among users.

 

Steve, W3AHL


Re: Strength of the IC7000

wb0m
 

Strength of the IC7000 
From: Bob Hoffmann, K4CQO

"I guess it makes sense to use the woodworking saying: "measure twice, cut once" for antenna connections -- the SWR of the units cannot be used to let you know if the right antenna is connected.

Hi Bob, 

Don’t worry:  You’re not alone. I’m a big user of the phrase “I cut it twice and it’s still too short”. (HI!). 

73,
Jeff/wb0m
Nebraska


Fabricate driver board ???

k2zc@...
 

I am repairing a radio for a friend. The driver board is burnt to a crisp the fet is literally welded to the heat sink. I'm aware that the board is no longer available. I am tempted to fabricate one from double sided pc board. It's not a complicated circuit. I'm curious if anyone else has tried this and been successful.


Re: Strength of the IC7000

 

HF to the outside, VHF to the inside. Probably better to color code the antenna leads maybe with inside VHF - outside HF


On Mon, Jun 1, 2020 at 8:28 AM Bob Hoffmann, K4CQO <rjhoffmann@...> wrote:
OK, I have to eat crow here, but wanted to saw how tolerant the IC7000 is and how well the MAT-TUNER mat-180H works. 

I do have the HF and VHF antennas labeled -- including the connectors and the coax, but after unplugging them for a lightening storm and reconnecting them, I manager to switch the whip that I use for VHF and Ultimax antenna that I use for HF. That went on for weeks -- actually do not remember how long it was switched.

I was wondering why the connection to the repeater was not going too well, and when I connected the HT for the DMR net and I could hear the connection very well, but when connecting to the repeater, I had lots of packet loss. The antenna tuner was able to get SWR to 1.5 for all of the bands -- including 160m -- while I was to the dual band 2m / 70 cm whip. I was surprised that I was able to get out at all!

Anyway, the IC7000 is doing fine, and now the S-meter is doing a lot better job of showing signals on HF than it was when connected to the dual band whip. I think that I need to put in a color coded label ... but I can say that the IC7000 and the antenna tuner are able to handle antennas that are no where near to the advertised bands without any apparent damage. I do have the power output set at 75-80%, but did put it up to 100% for the 2m net in order to be heard. I guess it makes sense to use the woodworking saying: "measure twice, cut once" for antenna connections -- the SWR of the units cannot be used to let you know if the right antenna is connected.



--
J.D. Barron


Strength of the IC7000

Bob Hoffmann, K4CQO
 

OK, I have to eat crow here, but wanted to saw how tolerant the IC7000 is and how well the MAT-TUNER mat-180H works. 

I do have the HF and VHF antennas labeled -- including the connectors and the coax, but after unplugging them for a lightening storm and reconnecting them, I manager to switch the whip that I use for VHF and Ultimax antenna that I use for HF. That went on for weeks -- actually do not remember how long it was switched.

I was wondering why the connection to the repeater was not going too well, and when I connected the HT for the DMR net and I could hear the connection very well, but when connecting to the repeater, I had lots of packet loss. The antenna tuner was able to get SWR to 1.5 for all of the bands -- including 160m -- while I was to the dual band 2m / 70 cm whip. I was surprised that I was able to get out at all!

Anyway, the IC7000 is doing fine, and now the S-meter is doing a lot better job of showing signals on HF than it was when connected to the dual band whip. I think that I need to put in a color coded label ... but I can say that the IC7000 and the antenna tuner are able to handle antennas that are no where near to the advertised bands without any apparent damage. I do have the power output set at 75-80%, but did put it up to 100% for the 2m net in order to be heard. I guess it makes sense to use the woodworking saying: "measure twice, cut once" for antenna connections -- the SWR of the units cannot be used to let you know if the right antenna is connected.


Rail mounts for IC-7000

George Kokolakis, SV3QUP
 

Hello to all,
I designed a pair of rails for my IC-7000 which can be either 3d printed or cut out of metal using a CNC. I have uploaded the desing to thingiverse here:https://www.thingiverse.com/thing:4405251.

73, SV3QUP George


Re: Seen these Auto ATU's

ronald keller
 






On Monday, May 25, 2020, 2:04 PM, montanaaardvark <boblombardi@...> wrote:

(I think I just hit a wrong button and got dumped - sorry if this is a dupe)

Do those "ATU-100 mini tuners by N7DDC" have a claimed impedance range?  You know, like the Icoms that have them have always claimed 3:1 VSWR.

I looked at a couple of eBay auctions and didn't see one.


Tnx,

Bob
--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for


Re: Seen these Auto ATU's

montanaaardvark
 

On Mon, May 25, 2020 at 09:09 PM, Charles & Sandra Cohen wrote:
FWIW --

There's an extensive write-up of this N7DDC auto-tuner here:

http://radioaficion.com/news/automatic-antenna-tuner-kit/

But it doesn't give an impedance range.

Neat unit . . .  I'm not giving up my LDG Z-11 Pro.
Thanks Charles - at least I'm feeling more like it's not my Search Engine ability that got no results.  I looked in several places.  They'll tell you the component size range, but that's all I've found.

I know what you mean about your Z-11 Pro.  My IC-7000 sits on the AT-7000 that LDG made specifically for the radio. 
 

Bob
--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for


Re: Seen these Auto ATU's

Charles & Sandra Cohen
 

FWIW --

There's an extensive write-up of this N7DDC auto-tuner here:

http://radioaficion.com/news/automatic-antenna-tuner-kit/

But it doesn't give an impedance range.

Neat unit . . .  I'm not giving up my LDG Z-11 Pro.

.   Charles / VA7CPC


Re: Seen these Auto ATU's

montanaaardvark
 

(I think I just hit a wrong button and got dumped - sorry if this is a dupe)

Do those "ATU-100 mini tuners by N7DDC" have a claimed impedance range?  You know, like the Icoms that have them have always claimed 3:1 VSWR.

I looked at a couple of eBay auctions and didn't see one.


Tnx,

Bob
--
W4ATM - 35 Miles south of the Kennedy Space Center
Retired RF Design Engineer
Now able to play with all the hobbies I never had enough time for


Re: Seen these Auto ATU's

Steve Sawicki
 

Interesting size and I like the power cell,can you provide the link as to the site.
Regards.
Steve
AB2ET

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