Date   

Re: low power out on HF

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@...>
Sent: 1/20/2021 6:38:08 AM
Subject: Re: [ic7000] low power out on HF

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@...>

Sent: 1/19/2021 8:26:21 AM

Subject: Re: [ic7000] low power out on HF

 

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. 


New CI-V Bluetooth Hub (CT17B-6BT) user manual published

VE2DX
 
Edited

Hey, guys please find on this link the updated CT17B-6BT CI-C Bluetooth Hub user manual updated with the IC-705 configuration procedure. can also be used to isolate the PC business of your shack from the RF side...

https://www.dropbox.com/s/jofwi7jlcti4rhu/CT-17B-6BT%20Manual%20Vers1_02_00%20%281%29.pdf?dl=0

(corrected the link sry :P )
--
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: low power out on HF

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@...>

Sent: 1/19/2021 8:26:21 AM

Subject: Re: [ic7000] low power out on HF

 

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. 


Re: low power out on HF

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...


Re: low power out on HF

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@...>
Sent: 1/19/2021 8:26:21 AM
Subject: Re: [ic7000] low power out on HF

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. 


low power out on HF

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


Re: low power out on HF

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. 


Re: low power out on HF

Sigi / DH1KLM
 

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.


Re: low power out on HF

Helmut Wabnig
 

On Tue, 19 Jan 2021 08:34:23 +0100, you wrote:

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
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

With the appropriate care, the 7000 is capable of working 100% power,
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


Re: low power out on HF

Ludovic Ludo
 

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

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


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. 


Re: VCTCXO model and the issue with crystal aging - 2LO off the DAC range

Steve W3AHL
 

Igor,

Good job!  Glad you were able to get the REF in spec with a simple change.

Steve, W3AHL


Re: VCTCXO model and the issue with crystal aging - 2LO off the DAC range

igor-m <mikki@...>
 

I applied my TCXO mod above and it seems it works!
I removed the R11 short and soldered in a 10k smd resistor at the pads of the not populated trimp pot.
The 10k resistor is easily accessible now as it sits on "top side" of the DDS pcb when mounted in.
I also covered the TCXO and the pcb from the opposite side with 3mm piece of foam (against the "banana effect").

The measurement is as follows now:

Service menu:
HEX        FREQ 2LO
00            124.031.190
7F            124.031.640
FF            124.032.120

I get the exact 2LO frequency of 124.032.000 Hz with E6 hex.

While measuring at the dummy load (with TX RTTY method) I get my 21.200.000 with 89% set in OTH menu #51.

73 Igor


Re: VCTCXO model and the issue with crystal aging - 2LO off the DAC range

igor-m <mikki@...>
 

Example: With R11 removed and the trimmpot soldered in (will be accessible from the top of the DDS board), for example 22k large, you may get following voltage ranges (the x-axis is the DAC output voltage from 00h to FFh, and the y-axis is the voltage at the CV pin of the TCXO):


Re: VCTCXO model and the issue with crystal aging - 2LO off the DAC range

igor-m <mikki@...>
 

On the DDS pcb - the position H10-V5 - you may find the pads for a smd pot trimmer (not populated), wired to the VC pin of the TCXO. They apparently planned to have a pot trim there in order to find a sweet spot for the voltage tuning range..


VCTCXO model and the issue with crystal aging - 2LO off the DAC range

igor-m <mikki@...>
 

Hi, as it has been discussed earlier I have been messing with the rather known potential issue - the TCXO's crystal aging.
The service menu REF hex value of FF does not tune my 2LO to the required 124.032MHz. Even with 100% OTH menu #51 I am still low by 5-10Hz at 21.2MHz.
I've made a model of the TCXO voltage tuning (based on the schematics in the Service Manual) and I've plotted the voltage range the 8bit DAC is producing at the TCXO's voltage control pin.The DAC is placed inside the HD64F2377 MCU.
It seems to me a potential solution could be a replacement of a resistor in the voltage divider - ie. the R10 with the stock value 22k (green) - after replaced by a larger value (ie. 27k, 33k) will shift the tuning voltage range such the TCXO will move higher with its frequency, imo.
Below the picture with the simulation.
PS: I would also increase the capacitor value there as the MCU's on-chip DACs are pretty noisy usually..
73 Igor


Re: IC7000 No power on, no relay click

Luc
 

Good evening to all..

finely i found the reason for no turning on of my 7000

R723 was broken..i measure 14v on the fuse site and only abbt 3v on the other side of the R.

so to low voltage on the regulator in the logic board...and no activation of q700 to pull the relais and give the HV line onn

Buth!!! the R has a value of 4.3ohm wen i measere him...silly!!

desolder him and he broke in 2 parts...so replaced bij a "ordinary" R and the 7000 is lighting and rx...

greeting


Re: LO off QRG

igor-m <mikki@...>
 

Steve, when you change the tuning voltage wired to the VCTCXO the TX frequency (measured with a counter at the dummy load) has to change too, imho. The 7000's firmware or hardware has not got any internal means how to determine "how much the frequency of the xtal has changed by applying certain voltage difference". There is none internal reference except the master VCTCXO oscillator.
Thus, when your external counter show 21.000.000 at the TX dummy load with "5F" hex, and you change it to "2C" you must see a change of the TX frequency after returning from the manufacturing menu. The important assumption is there is the "VC" TXCO module soldered on the board, the DAC works and the firmware has not got a bug as well.
Would be great if we will come to an understanding "how the stuff works", as this is a topic people here discussing for a decade already :)


Re: LO off QRG

Steve W3AHL
 

Igor,

There is much that goes on in the firmware that makes it hard to predict how the hardware will work.  But the behavior you see is normal.  Setting the REF frequency accurately will either solve your problem or tell you there is a problem with the oscillator or the control voltage from the CPU.

Your unit's hex value for REF of 9B is higher than typical in the four radios I have recorded the values for ((typically 55-76), but accurate measurement is the only way to set the frequency so that the IF stages work corrrectly.

Steve, W3AHL


Re: LO off QRG

igor-m <mikki@...>
 

On Sat, Jan 9, 2021 at 09:52 PM, Steve W3AHL wrote:

..
In Maintenance mode, adjusting the REF setting from 0-FF changes the 124.032 MHz 2LO by 1300 Hz, but does not affect the TX frequency when returned to normal mode -- just as you saw.
I don't have an explanation for why it behaves that way.  ..

I've asked Icom Europe on this (a week back), none answer yet.
My gut feeling tells me the change of the maintenance mode REF setting from 0-FF must change the TX frequency in AM CW RTTY modes, provided you do not touch the OTH #51.
If the the maintenance mode REF setting from 0-FF "really changes the control voltage of the VCTCXO" then your TX frequency must change accordingly.
No way it stays the same after the return to the normal mode..
Igor

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