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...
Posted: Wed Oct 13, 2010 11:10 am
 
Hi,

I recently bought an Icom IC-7000 transceiver from the estate of a
"silent key". The UHF power output, although the radio is set to
"100 percent power" (all bands), puts out about 50 percent on the
UHF band. UHF watt meter indicates around 18 watts when it
should be 35 watts. Note: Other bands are just fine at 100 percent.

I downloaded the service manual from www.mods.dk and followed
the procedure to enter the "Adjustment" mode. However, I can not
change any settings beyond the "Total Gain (430)! My intention
was to increase the "100 percent" value, which is beyond the "Total Gain"
adjustments, to see if the power goes up. Note: I am using a proper dummy
load.

I couldn't find in the service manual or service manual addendum
any information regarding this issue.

By any chance, did you encounter the same situation?

Thank You in Advance, John N3AOF

PS, Remove "ine" from my email address
 
Jerry G....
Posted: Fri Oct 15, 2010 5:37 am
 
Do a web search for iCom. They will answer your questions...

I would suspect a problem in the final output, or in the drivers. If
you have the service manual, follow through by verifying the supply
voltages to the final and modulator sections. Also, verify the
carrier amplitude.

I don't know the unit, but also check in the user book to see if there
are any settings for reduced power output.

I am assuming that all the standard procedures of antenna match and
etc has been done...


Jerry G.



On Oct 13, 1:10 pm, jaugust... at (no spam) verizon.net wrote:
[quote]Hi,

     I recently bought an Icom IC-7000 transceiver from the estate of a
"silent key".   The UHF power output, although the radio is set to
"100 percent power" (all bands), puts out about 50 percent on the
UHF band.   UHF watt meter indicates around 18 watts when it
should be 35 watts.  Note: Other bands are just fine at 100 percent.

    I downloaded the service manual fromwww.mods.dkand followed
the procedure to enter the "Adjustment" mode.  However,  I can not
change any settings beyond the "Total Gain (430)!   My intention
was to increase the "100 percent" value, which is beyond the "Total Gain"
adjustments,  to see if the power goes up.   Note: I am using a proper dummy
load.

     I couldn't find in the service manual or service manual addendum
any information regarding this issue.

     By any chance, did you encounter the same situation?

       Thank You in Advance,  John N3AOF

PS,  Remove "ine" from my email address[/quote]
 
Meat Plow...
Posted: Fri Oct 15, 2010 6:05 am
 
On Fri, 15 Oct 2010 08:37:50 -0700, Jerry G. wrote:

[quote]Do a web search for iCom. They will answer your questions...

I would suspect a problem in the final output, or in the drivers. If you
have the service manual, follow through by verifying the supply voltages
to the final and modulator sections. Also, verify the carrier
amplitude.

I don't know the unit, but also check in the user book to see if there
are any settings for reduced power output.

I am assuming that all the standard procedures of antenna match and etc
has been done...
[/quote]
1. Make sure the SWR on the UHF antenna is 1.5:1 or below. If ok it could
be the hybrid output device. Not knowing the 7000 I would assume that it
would have a separate output device for UHF. However I would verify the
power input to the device and its voltage and AGC circuits before deeming
it bad.



--
Live Fast, Die Young and Leave a Pretty Corpse
 
Fred McKenzie...
Posted: Fri Oct 15, 2010 6:44 pm
 
In article <0upbb61jot8ptbsgn6rac15r71pri1qvdh at (no spam) 4ax.com>,
jaugustine at (no spam) verizon.net wrote:

[quote]I downloaded the service manual from www.mods.dk and followed
the procedure to enter the "Adjustment" mode.
[/quote]
John-

If I understand, you are trying to increase power beyond 100%. My
thought is that you are getting all you can with the hardware you have.
The hardware may be defective and the computer can't compensate for that.

My problem is with frequency adjustment. When I enter the Adjustment
mode, I can set the oscillator frequency to exactly what it should be.
However, frequency returns to the previous value when I leave the
Adjustment mode. If I re-enter Adjustment mode, the oscillator
frequency goes back to the correct value, and again reverts when exiting
Adjustment mode.

Do you or anyone else know what I might be doing wrong? Is there a step
I'm missing that makes changes "take"?

Fred
K4DII
 
...
Posted: Sat Oct 16, 2010 6:12 am
 
Hi Fred,

I should have said the UHF is set to "100%", but it is putting out
around 50 percent.

I am sorry Fred, I have no idea why you are having that issue with
the frequency adjustment. I am assuming, after you adjusted, you pressed "F-4
(SET).

Would you please tell me if you can change the value on the display
beyond the "Total Gain"? Simply rotate the main Dial and see if the
number changes. On my IC-7000, no change occurs.

Thank You in advance, John N3AOF


On Fri, 15 Oct 2010 20:44:31 -0400, in sci.electronics.repair you wrote:

[quote]In article <0upbb61jot8ptbsgn6rac15r71pri1qvdh at (no spam) 4ax.com>,
jaugustine at (no spam) verizon.net wrote:

I downloaded the service manual from www.mods.dk and followed
the procedure to enter the "Adjustment" mode.

John-

If I understand, you are trying to increase power beyond 100%. My
thought is that you are getting all you can with the hardware you have.
The hardware may be defective and the computer can't compensate for that.

My problem is with frequency adjustment. When I enter the Adjustment
mode, I can set the oscillator frequency to exactly what it should be.
However, frequency returns to the previous value when I leave the
Adjustment mode. If I re-enter Adjustment mode, the oscillator
frequency goes back to the correct value, and again reverts when exiting
Adjustment mode.

Do you or anyone else know what I might be doing wrong? Is there a step
I'm missing that makes changes "take"?

Fred
K4DII[/quote]
 
Fred McKenzie...
Posted: Sat Oct 16, 2010 5:05 pm
 
In article <uh5jb6tocoigv48v713k007rt9334q7k22 at (no spam) 4ax.com>,
jaugustine at (no spam) verizon.net wrote:

[quote]Would you please tell me if you can change the value on the display
beyond the "Total Gain"? Simply rotate the main Dial and see if the
number changes. On my IC-7000, no change occurs.
[/quote]
John-

I don't have the ability to inject 3mV at (no spam) 1.5KHz into the microphone
connector. Therefore I get zero output unless I speak or whistle into
the microphone. Just rotating the main dial makes no difference. I
don't see a number, just the output scale that reads up to 100.

I see that for "TX Total Gain(430M)", the correct output setting is 17.5
Watts. It isn't until a later step that you set (Po Max(430M) for 35
Watts.

If you can't get the power up to either value, the UHF amplifier module
may have a problem. Since it isn't completely dead, you may decide to
keep it that way rather than pay the price for a replacement. I
wouldn't be surprised if you can buy a used IC-7000 for little more than
the price of the module!

I'm sure I pressed the "F-4 (SET)" button. I suppose there could be a
firmware upgrade needed.

Fred
K4DII

--- news://freenews.netfront.net/ - complaints: news at (no spam) netfront.net ---
 
...
Posted: Sun Oct 17, 2010 10:13 am
 
Hi Fred,

Just to see if the number, which is hexadecimal (digits from 0 - 9 plus
A - F) changes located above the F1, F2 buttons, by turning the Dial,
you don't need to input an audio tone. You need the tone to check the
new setting afterwards on a watt meter.

FYI:

On my display are the following (via TX adjustments)
for "PO" on 430M:

07 MIN

47 00DF 25%

71 019F 50%

0292 100%

B4 MAX


What are your numbers? I just want to see if they are far off from
mine.

Thank You Again, John N3AOF


On Sat, 16 Oct 2010 19:05:05 -0400, in sci.electronics.repair you wrote:

[quote]In article <uh5jb6tocoigv48v713k007rt9334q7k22 at (no spam) 4ax.com>,
jaugustine at (no spam) verizon.net wrote:

Would you please tell me if you can change the value on the display
beyond the "Total Gain"? Simply rotate the main Dial and see if the
number changes. On my IC-7000, no change occurs.

John-

I don't have the ability to inject 3mV at (no spam) 1.5KHz into the microphone
connector. Therefore I get zero output unless I speak or whistle into
the microphone. Just rotating the main dial makes no difference. I
don't see a number, just the output scale that reads up to 100.

I see that for "TX Total Gain(430M)", the correct output setting is 17.5
Watts. It isn't until a later step that you set (Po Max(430M) for 35
Watts.

If you can't get the power up to either value, the UHF amplifier module
may have a problem. Since it isn't completely dead, you may decide to
keep it that way rather than pay the price for a replacement. I
wouldn't be surprised if you can buy a used IC-7000 for little more than
the price of the module!

I'm sure I pressed the "F-4 (SET)" button. I suppose there could be a
firmware upgrade needed.

Fred
K4DII

--- news://freenews.netfront.net/ - complaints: news at (no spam) netfront.net ---[/quote]
 
Fred McKenzie...
Posted: Sun Oct 17, 2010 10:34 pm
 
In article <u18mb65dtmj0q29kvcdisbpnm9113set6n at (no spam) 4ax.com>,
jaugustine at (no spam) verizon.net wrote:

[quote]Just to see if the number, which is hexadecimal (digits from 0 - 9 plus
A - F) changes located above the F1, F2 buttons, by turning the Dial,
you don't need to input an audio tone.
[/quote]
John-

Now I see what you are getting at. The Hex digits did not change when I
turned the dial.

My numbers for 430M:

MIN 08
25% 41 00C8
50% 6B 018C
100% 0273
MAX A8

I checked power output on 430 (23 Watts) and 146 MHz (35 Watts) in FM
mode. I did not check voltage under load. I'm using a little MFJ-4125P
25 Amp switching supply.

Do you know if there has been a firmware upgrade for this radio?

Fred
K4DII
 
...
Posted: Mon Oct 18, 2010 10:08 am
 
Hi Fred,

Thanks for the Watt report on your radio. I assume you used a
low SWR antenna or a wide frequency range quality dummy load.

Since I recently purchased this IC-7000 from the estate of a SK,
I am unaware of a firmware upgrade, but it might be a good idea to
check the Icom forum, if there is one at Icom's web site?

I will be checking for one in the next day or so.

Again Thank You, John N3AOF


On Mon, 18 Oct 2010 00:34:01 -0400, in sci.electronics.repair you wrote:

[quote]In article <u18mb65dtmj0q29kvcdisbpnm9113set6n at (no spam) 4ax.com>,
jaugustine at (no spam) verizon.net wrote:

Just to see if the number, which is hexadecimal (digits from 0 - 9 plus
A - F) changes located above the F1, F2 buttons, by turning the Dial,
you don't need to input an audio tone.

John-

Now I see what you are getting at. The Hex digits did not change when I
turned the dial.

My numbers for 430M:

MIN 08
25% 41 00C8
50% 6B 018C
100% 0273
MAX A8

I checked power output on 430 (23 Watts) and 146 MHz (35 Watts) in FM
mode. I did not check voltage under load. I'm using a little MFJ-4125P
25 Amp switching supply.

Do you know if there has been a firmware upgrade for this radio?

Fred
K4DII[/quote]
 
...
Posted: Tue Oct 19, 2010 10:41 am
 
Hi,

UPDATE:

Well it looks like I have evidence that the problem may be the final amp
or associated circuit. In the "Adjustment mode", I checked the idle current
(transmit SSB without modulation with a current meter in the power supply line
as described in the SM. For HF/50M and 144M against a "00" setting reference
(as described in the SM), the current was higher by the specified amount
compared to the "00" reference. However, for 430M, the idle current is the
same as the "00" reference, and it can not be increase (in transmit) to the
value specified in the SM. Rotating the adjustment dial, which shows a
change in the number, has no effect on the idle current.

I will not pursue this any further at this time. I am able to use
430 MHZ SSB, but at a lower power level (around 18W).

Thanks to everyone for your useful suggestions.

John N3AOF


On Wed, 13 Oct 2010 13:10:28 -0400, in sci.electronics.repair you wrote:

[quote]Hi,

I recently bought an Icom IC-7000 transceiver from the estate of a
"silent key". The UHF power output, although the radio is set to
"100 percent power" (all bands), puts out about 50 percent on the
UHF band. UHF watt meter indicates around 18 watts when it
should be 35 watts. Note: Other bands are just fine at 100 percent.

I downloaded the service manual from www.mods.dk and followed
the procedure to enter the "Adjustment" mode. However, I can not
change any settings beyond the "Total Gain (430)! My intention
was to increase the "100 percent" value, which is beyond the "Total Gain"
adjustments, to see if the power goes up. Note: I am using a proper dummy
load.

I couldn't find in the service manual or service manual addendum
any information regarding this issue.

By any chance, did you encounter the same situation?

Thank You in Advance, John N3AOF

PS, Remove "ine" from my email address

[/quote]
 
Jeff Liebermann...
Posted: Wed Oct 20, 2010 12:41 am
 
On Tue, 19 Oct 2010 12:41:23 -0400, jaugustine at (no spam) verizon.net wrote:

[quote]Well it looks like I have evidence that the problem may be the final amp
or associated circuit. In the "Adjustment mode", I checked the idle current
(transmit SSB without modulation with a current meter in the power supply line
as described in the SM. For HF/50M and 144M against a "00" setting reference
(as described in the SM), the current was higher by the specified amount
compared to the "00" reference. However, for 430M, the idle current is the
same as the "00" reference, and it can not be increase (in transmit) to the
value specified in the SM. Rotating the adjustment dial, which shows a
change in the number, has no effect on the idle current.

I will not pursue this any further at this time. I am able to use
430 MHZ SSB, but at a lower power level (around 18W).
[/quote]
Kinda looks like the RD60HUF1 RF output xistor might be toast. The
Vgs bias adjustment is a DC characteristic, and does not require any
RF drive to function. See Pg 2/7 which shows the Vgs to Igs graph. At
Ids=2.5A, Vgs should be 2.5 volts. You can measure that with a
volts-guesser by simply removing the bottom cover:
<http://www.rfparts.com/pdf_docs/RD/rd60huf1.pdf>
$29.20 from RF Parts.


--
Jeff Liebermann jeffl at (no spam) cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
 
 
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