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Old January 30th 15, 08:30 AM posted to rec.radio.amateur.equipment
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Posts: 6
Default Yaesu FT-991 AM transmission defective

My initial testing on an FT-991 I bought Tuesday indictaes AM
transmission is severely distorted. I tried everything in the manual
that seemed relevant to AM transmission without any improvement.

Transmitting into a Cobra Senior perfectly matched with a Nye Viking MBII
on 3885 showed pronounced downward modulation even on a peak reading
MFJ 870 meter. Normally a peak reading watt meter will show strong upward
movement as the peak power is 4 times carrier power.

I called Yaesu tech support. The tech was not aware of any prolbems with
AM on the 991. He suggested I reset the processor.

After the processor reset returned the 991 to its factory defaults, the
3885 morning crowd confirmed the transmitted signal was still terrible.

I have been able to get good results transmitting AM with many oher
radios including IC706mkiiG, 756Pro, and FlexRadio 5000a.

A quick check on 2 meters showed the same profound downward modulation
on the FT-991.

Anyone having better luck with AM on the FT-991?

-de WA7KGX
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Old February 2nd 15, 11:34 PM posted to rec.radio.amateur.equipment
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First recorded activity by RadioBanter: Jul 2006
Posts: 317
Default Yaesu FT-991 AM transmission defective

In article ,
wa7kgx wrote:

My initial testing on an FT-991 I bought Tuesday indictaes AM
transmission is severely distorted. I tried everything in the manual
that seemed relevant to AM transmission without any improvement.

Transmitting into a Cobra Senior perfectly matched with a Nye Viking MBII
on 3885 showed pronounced downward modulation even on a peak reading
MFJ 870 meter. Normally a peak reading watt meter will show strong upward
movement as the peak power is 4 times carrier power.

I called Yaesu tech support. The tech was not aware of any prolbems with
AM on the 991. He suggested I reset the processor.

After the processor reset returned the 991 to its factory defaults, the
3885 morning crowd confirmed the transmitted signal was still terrible.

I have been able to get good results transmitting AM with many oher
radios including IC706mkiiG, 756Pro, and FlexRadio 5000a.

A quick check on 2 meters showed the same profound downward modulation
on the FT-991.

Anyone having better luck with AM on the FT-991?


WA7KGX-

I have the same problem with my FT-991, with the Po Meter kicking
downward with modulation. The manual’s procedure for setting AM
Microphone gain does not work. They instruct you to adjust so ALC does
not deflect when speaking. If you do that, there is no modulation. The
ALC meter has a static level that kicks upward with modulation.

It might help if we compared notes on other problems. From what I can
tell, both the hardware and firmware have bugs. Here are some other
problems I've found:

1. On several occasions the radio has locked-up, stopped receiving or
refused to transmit. Recycling power cleared up the problem.

2. On 14, 50 and 430 MHz SSB, the ALC Meter reading is missing,
depending on antenna SWR. On 14 and 50 it only works if SWR is high, on
430 if it is low.

3. If you look at the left side of the display, you may see IPO, AMP1
or AMP2 listed. It depends on the IPO setting on HF. AMP1 and AMP2 do
not apply to VHF or UHF. They may appear there as well, and can only be
changed by re-programming the frequency. If you select an HF frequency
in VFO mode, you can turn the AMPs on and off. Whatever state they are
in, remains if you then select BAND - ENT and enter a VHF or UHF
frequency.

4. The 5/10 Hz setting is stuck on 5 Hz for AM, FM, C4FM and DATA-FM
modes. Main-dial frequency step is 100Hz, but CLARifier is 5 Hz.

5. In order to use a program like CHIRP to program the radio, it is
necessary to start up the radio in Clone mode The manual is missing
information on CAT and Cloning. FT-817/857/897 Clone setup does not
work with the FT-991, which is missing the two Mode buttons.

I would be interested in knowing if you have observed any of these
problems in your FT-991.

Fred
K4DII
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Old February 3rd 15, 12:12 AM posted to rec.radio.amateur.equipment
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First recorded activity by RadioBanter: Jan 2015
Posts: 6
Default Yaesu FT-991 AM transmission defective

On Mon, 02 Feb 2015 18:34:02 -0500, Fred McKenzie wrote:

In article ,
wa7kgx wrote:

My initial testing on an FT-991 I bought Tuesday indictaes AM
transmission is severely distorted. I tried everything in the manual
that seemed relevant to AM transmission without any improvement.

Transmitting into a Cobra Senior perfectly matched with a Nye Viking
MBII on 3885 showed pronounced downward modulation even on a peak
reading MFJ 870 meter. Normally a peak reading watt meter will show
strong upward movement as the peak power is 4 times carrier power.

I called Yaesu tech support. The tech was not aware of any prolbems
with AM on the 991. He suggested I reset the processor.

After the processor reset returned the 991 to its factory defaults, the
3885 morning crowd confirmed the transmitted signal was still terrible.

I have been able to get good results transmitting AM with many oher
radios including IC706mkiiG, 756Pro, and FlexRadio 5000a.

A quick check on 2 meters showed the same profound downward modulation
on the FT-991.

Anyone having better luck with AM on the FT-991?


WA7KGX-

I have the same problem with my FT-991, with the Po Meter kicking
downward with modulation. The manual’s procedure for setting AM
Microphone gain does not work. They instruct you to adjust so ALC does
not deflect when speaking. If you do that, there is no modulation. The
ALC meter has a static level that kicks upward with modulation.

It might help if we compared notes on other problems. From what I can
tell, both the hardware and firmware have bugs. Here are some other
problems I've found:

1. On several occasions the radio has locked-up, stopped receiving or
refused to transmit. Recycling power cleared up the problem.

2. On 14, 50 and 430 MHz SSB, the ALC Meter reading is missing,
depending on antenna SWR. On 14 and 50 it only works if SWR is high, on
430 if it is low.

3. If you look at the left side of the display, you may see IPO, AMP1
or AMP2 listed. It depends on the IPO setting on HF. AMP1 and AMP2 do
not apply to VHF or UHF. They may appear there as well, and can only be
changed by re-programming the frequency. If you select an HF frequency
in VFO mode, you can turn the AMPs on and off. Whatever state they are
in, remains if you then select BAND - ENT and enter a VHF or UHF
frequency.

4. The 5/10 Hz setting is stuck on 5 Hz for AM, FM, C4FM and DATA-FM
modes. Main-dial frequency step is 100Hz, but CLARifier is 5 Hz.

5. In order to use a program like CHIRP to program the radio, it is
necessary to start up the radio in Clone mode The manual is missing
information on CAT and Cloning. FT-817/857/897 Clone setup does not
work with the FT-991, which is missing the two Mode buttons.

I would be interested in knowing if you have observed any of these
problems in your FT-991.

Fred K4DII


Based on previous experience reviewing the Yaesu Spirit ham/aviation
handheld for Aviation Consumer and W7WAA's commenta on the Yaesu
FTDX-1200, I decided not to wait for a miracle to happen soon at Yaesu
and took the FT-991 back to HRO and insisted on getting my money back.
The radio does not meet its advertised description.
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Old February 12th 15, 10:47 PM posted to rec.radio.amateur.equipment
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Posts: 6
Default Yaesu FT-991 AM transmission defective

The air checks are available at http:www.omen.com/waykgx/ham.html

For some reason I couldn't post the sound files to the newsgroup with PAN.
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Old February 13th 15, 06:30 AM posted to rec.radio.amateur.equipment
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First recorded activity by RadioBanter: Jul 2006
Posts: 317
Default Yaesu FT-991 AM transmission defective

In article ,
wa7kgx wrote:

The air checks are available at http:www.omen.com/waykgx/ham.html

For some reason I couldn't post the sound files to the newsgroup with PAN.


WA7KGX-

Some news servers do not accept files.

I saw your comments on the eHam net forum.

I have a list of several problems with my FT-991, including the
defective AM. There are some things I like about the radio, so I prefer
to get it repaired rather than getting a refund.

The reason AM power is set to 25 Watts, is that the radio is only
capable of 100 Watts. One hundred Watts is the peak power of a 100
percent modulated 25 Watt AM signal. The FT-991 Po meter should kick
from 25 Watts to nearly 100 watts on voice peaks. Mine kicks downward
instead.

If you can not get a refund, I suggest you also take the "repair"
approach. There is no reason the radio should not produce an acceptable
AM signal. It almost certainly is misaligned, and can be corrected. If
Yaesu can not correct the problem by alignment, then they should replace
the defective module.

With regard to your other comment about listening to a repeater's input
frequency, you can easily do that with the REV function. You will
notice that it changes the memory contents, so you must press the REV a
second time to return to normal frequencies.

That is one of my minor gripes about the radio, that some functions
directly affect memory, rather than a "working copy" of the memory.

73,
Fred
K4DII


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Old February 13th 15, 08:30 AM posted to rec.radio.amateur.equipment
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Posts: 6
Default Yaesu FT-991 AM transmission defective

On Fri, 13 Feb 2015 01:30:16 -0500, Fred McKenzie wrote:

In article ,
wa7kgx wrote:

The air checks are available at http:www.omen.com/waykgx/ham.html

For some reason I couldn't post the sound files to the newsgroup with
PAN.


WA7KGX-

Some news servers do not accept files.

I saw your comments on the eHam net forum.

I have a list of several problems with my FT-991, including the
defective AM. There are some things I like about the radio, so I prefer
to get it repaired rather than getting a refund.

The reason AM power is set to 25 Watts, is that the radio is only
capable of 100 Watts. One hundred Watts is the peak power of a 100
percent modulated 25 Watt AM signal. The FT-991 Po meter should kick
from 25 Watts to nearly 100 watts on voice peaks. Mine kicks downward
instead.

If you can not get a refund, I suggest you also take the "repair"
approach. There is no reason the radio should not produce an acceptable
AM signal. It almost certainly is misaligned, and can be corrected. If
Yaesu can not correct the problem by alignment, then they should replace
the defective module.

With regard to your other comment about listening to a repeater's input
frequency, you can easily do that with the REV function. You will
notice that it changes the memory contents, so you must press the REV a
second time to return to normal frequencies.

That is one of my minor gripes about the radio, that some functions
directly affect memory, rather than a "working copy" of the memory.

73,
Fred K4DII


First time I tried using REV: set fm repeater 145.29 rpt - offset.
REV made a sound but did nothing.

Did a full processor reset, same result.
Then on a hunch I set repeater offset to + and voila! REV works.

This is one buggy radio.
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Old December 28th 15, 03:48 AM posted to rec.radio.amateur.equipment
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Posts: 3
Default Yaesu FT-991 AM transmission defective

On Friday, January 30, 2015 at 2:30:06 AM UTC-6, wa7kgx wrote:
My initial testing on an FT-991 I bought Tuesday indictaes AM
transmission is severely distorted. I tried everything in the manual
that seemed relevant to AM transmission without any improvement.

Transmitting into a Cobra Senior perfectly matched with a Nye Viking MBII
on 3885 showed pronounced downward modulation even on a peak reading
MFJ 870 meter. Normally a peak reading watt meter will show strong upward
movement as the peak power is 4 times carrier power.

I called Yaesu tech support. The tech was not aware of any prolbems with
AM on the 991. He suggested I reset the processor.

After the processor reset returned the 991 to its factory defaults, the
3885 morning crowd confirmed the transmitted signal was still terrible.

I have been able to get good results transmitting AM with many oher
radios including IC706mkiiG, 756Pro, and FlexRadio 5000a.

A quick check on 2 meters showed the same profound downward modulation
on the FT-991.

Anyone having better luck with AM on the FT-991?

-de WA7KGX


I just got the FT-991, and have the same poor audio on transmission in AM mode. Has there been any luck in finding a fix?
Thanks,
N4RCC, Richard
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Old January 22nd 16, 04:00 PM posted to rec.radio.amateur.equipment
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Posts: 3
Default Yaesu FT-991 AM transmission defective

On Sunday, December 27, 2015 at 10:48:46 PM UTC-5, N4RCC - Richard wrote:
On Friday, January 30, 2015 at 2:30:06 AM UTC-6, wa7kgx wrote:
My initial testing on an FT-991 I bought Tuesday indictaes AM
transmission is severely distorted. I tried everything in the manual
that seemed relevant to AM transmission without any improvement.

Transmitting into a Cobra Senior perfectly matched with a Nye Viking MBII
on 3885 showed pronounced downward modulation even on a peak reading
MFJ 870 meter. Normally a peak reading watt meter will show strong upward
movement as the peak power is 4 times carrier power.

I called Yaesu tech support. The tech was not aware of any prolbems with
AM on the 991. He suggested I reset the processor.

After the processor reset returned the 991 to its factory defaults, the
3885 morning crowd confirmed the transmitted signal was still terrible.

I have been able to get good results transmitting AM with many oher
radios including IC706mkiiG, 756Pro, and FlexRadio 5000a.

A quick check on 2 meters showed the same profound downward modulation
on the FT-991.

Anyone having better luck with AM on the FT-991?

-de WA7KGX


I just got the FT-991, and have the same poor audio on transmission in AM mode. Has there been any luck in finding a fix?
Thanks,
N4RCC, Richard


I have same problem with my 991 bought in June 15.it sound a little better when I use MD100 desk mic on hi emphasis
Bob Meyer WA9M
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Old February 8th 16, 08:13 PM posted to rec.radio.amateur.equipment
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First recorded activity by RadioBanter: Feb 2016
Posts: 1
Default Yaesu FT-991 AM transmission defective

Dr OM,

It's likeley that the AM carrier level in the service menu is set wrong. Maybe interesting to read: http://www.amateurtele.com/index.php...el=168&id=#752 This is an article about the FT-991 and how to adjust the AM carrier level.

73 de PE2CJ.
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Old February 10th 16, 05:28 PM posted to rec.radio.amateur.equipment
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First recorded activity by RadioBanter: Jan 2016
Posts: 3
Default Yaesu FT-991 AM transmission defective

On Monday, February 8, 2016 at 3:13:48 PM UTC-5, wrote:
Dr OM,

It's likeley that the AM carrier level in the service menu is set wrong. Maybe interesting to read: http://www.amateurtele.com/index.php...el=168&id=#752 This is an article about the FT-991 and how to adjust the AM carrier level.

73 de PE2CJ.


GM OM
With my 991 I cannot set the alc level it is at max no matter where the carrier level or mic gain is set on 6m.On hf bands it seems to work properly u can set the alc level.I have not been able to get audio rpts on 10 AM yet.
I am wondering if there are enough complaints to Yaesu if they will look in to problem.Probably maybe a recall would be in order,that would invole sending radios back to factory.
I have been on website and left a email,but have had no reply.I think a phone call from 991 owners might alert them to the problem.

73 Bob WA9M


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