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Yamaha CM500

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Jim Brown-10

Re: Yamaha CM500

On 11/19/2010 6:23 PM, Luis V. Romero wrote:
> These Orions are really bassy.

I understand. Makes you appreciate the K3 even more -- no need for the
W2IHY unit, or for external EQ.

Take a look at the simple circuit that Joe, W4TV, posted yesterday.
It's a very old broadcast engineering technique that we both remembered.
I've used the series capacitor when I wanted to use other pro mics with
ham rigs that lacked mic EQ, and it worked quite well. You'll see that
in the Ham Interfacing tutorial that I posted to my website several
years ago. The cap is for LF rolloff, not DC blocking (which is not
needed). The only trick is finding the small cap needed to fit inside
the connector.

73, Jim K9YC
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riese-k3djc

Re: Yamaha CM500

In reply to this post by VK1DW

boy that idea takes you back,, some surplus (ww2) receivers used dc on
the filaments
so when you ran them on ac there was residual hum and a series cap in the
speaker lead
took care of that
bob K3DJC

rb
On Sat, 20 Nov 2010 09:35:01 -0800 Jim Brown <[hidden email]>
writes:

> On 11/19/2010 6:23 PM, Luis V. Romero wrote:
> > These Orions are really bassy.
>
> I understand. Makes you appreciate the K3 even more -- no need for
> the
> W2IHY unit, or for external EQ.
>
> Take a look at the simple circuit that Joe, W4TV, posted yesterday.
>
> It's a very old broadcast engineering technique that we both
> remembered.
> I've used the series capacitor when I wanted to use other pro mics
> with
> ham rigs that lacked mic EQ, and it worked quite well. You'll see
> that
> in the Ham Interfacing tutorial that I posted to my website several
>
> years ago. The cap is for LF rolloff, not DC blocking (which is not
>
> needed). The only trick is finding the small cap needed to fit
> inside
> the connector.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>

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Joe Subich, W4TV-4

Re: Yamaha CM500

In reply to this post by Jim Brown-10

> It's a very old broadcast engineering technique that we both
> remembered. I've used the series capacitor when I wanted to use other
> pro mics with ham rigs that lacked mic EQ, and it worked quite well.

In this case, the value is chosen in conjunction with the shunt
resistor to provide the 16 to 20 dB pad to bring the CM-500 level
down to something more like what Yaesu expects to see. It provides
a dual function ... both level matching and response shaping.

> The cap is for LF rolloff, not DC blocking (which is not needed).

It's not needed for blocking in Yaesu rigs. However, some other
manufacturers do not include a blocking capacitor and failing to
include one in a "DC adder" for an electret mic (or FET preamp)
can upset the bias of the rig's mic preamp.

73,

... Joe, W4TV

On 11/20/2010 12:35 PM, Jim Brown wrote:

> On 11/19/2010 6:23 PM, Luis V. Romero wrote:
>> These Orions are really bassy.
>
> I understand. Makes you appreciate the K3 even more -- no need for the
> W2IHY unit, or for external EQ.
>
> Take a look at the simple circuit that Joe, W4TV, posted yesterday.
> It's a very old broadcast engineering technique that we both remembered.
> I've used the series capacitor when I wanted to use other pro mics with
> ham rigs that lacked mic EQ, and it worked quite well. You'll see that
> in the Ham Interfacing tutorial that I posted to my website several
> years ago. The cap is for LF rolloff, not DC blocking (which is not
> needed). The only trick is finding the small cap needed to fit inside
> the connector.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

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Eric-2

Hello Test again

test
--
Eric P. Nichols, KL7AJ, NNN0AKA, WD2XSH/27
P.O. Box 56235
North Pole, AK 99705
(907) 488-0483
[hidden email]
[hidden email]
[hidden email]
http://ericnichols.net
On Saturday 20 November 2010 09:04:51 am Joe Subich, W4TV wrote:

> > It's a very old broadcast engineering technique that we both
> > remembered. I've used the series capacitor when I wanted to use other
> > pro mics with ham rigs that lacked mic EQ, and it worked quite well.
>
> In this case, the value is chosen in conjunction with the shunt
> resistor to provide the 16 to 20 dB pad to bring the CM-500 level
> down to something more like what Yaesu expects to see. It provides
> a dual function ... both level matching and response shaping.
>
> > The cap is for LF rolloff, not DC blocking (which is not needed).
>
> It's not needed for blocking in Yaesu rigs. However, some other
> manufacturers do not include a blocking capacitor and failing to
> include one in a "DC adder" for an electret mic (or FET preamp)
> can upset the bias of the rig's mic preamp.
>
> 73,
>
> ... Joe, W4TV
>
> On 11/20/2010 12:35 PM, Jim Brown wrote:
> > On 11/19/2010 6:23 PM, Luis V. Romero wrote:
> >> These Orions are really bassy.
> >
> > I understand. Makes you appreciate the K3 even more -- no need for the
> > W2IHY unit, or for external EQ.
> >
> > Take a look at the simple circuit that Joe, W4TV, posted yesterday.
> > It's a very old broadcast engineering technique that we both remembered.
> > I've used the series capacitor when I wanted to use other pro mics with
> > ham rigs that lacked mic EQ, and it worked quite well. You'll see that
> > in the Ham Interfacing tutorial that I posted to my website several
> > years ago. The cap is for LF rolloff, not DC blocking (which is not
> > needed). The only trick is finding the small cap needed to fit inside
> > the connector.
> >
> > 73, Jim K9YC
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
>
> ______________________________________________________________
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AC7AC

Re: Yamaha CM500

In reply to this post by Jim Brown-10

CONTENTS DELETED

The author has deleted this message.

Joe Subich, W4TV-4

Re: Yamaha CM500

>0.047 uF such as Joe noted was common but sometimes as little as
> 0.001 uF, depending upon the impedances involved and the amount of
> roll-off wanted.

0.047 uF was common for "mild presence" in high impedance (50 K)
mic circuits with tube radios. 0.001 uF was the "contester/DXer"
trick - similar to the Heil HC 4 element today.

The legacy of selecting capacitors to shape microphone response can
still be seen in the response switches in Yaesu microphones like
the Yaesu MH-1, MH-31 and MD-1. The series capacitor values are
typically 10 times greater than those used with "high impedance"
mics ... e.g. 1 to 5 uF = "flat", .33 to .47 uF for modest boost
("HC-5") and .1 uF for "DX" ("HC-4") but they perform the same
function.

The series capacitor is particularly useful to counteract the
proximity effect (base boost) when a mic is used close to the
mouth.

73,

... Joe, W4TV

On 11/20/2010 1:30 PM, Ron D'Eau Claire wrote:

> Common Ham and general communications transmitter designs with vacuum tubes
> also used very small coupling capacitors between the speech (audio)
> amplifier stages for the same reason. 0.047 uF such as Joe noted was common
> but sometimes as little as 0.001 uF, depending upon the impedances involved
> and the amount of roll-off wanted.
>
> They also frequently employed smaller cathode bypass capacitors than normal,
> which further reduced bass response and introduced some negative feedback to
> help stage linearity, but the greatest frequency shaping in the pre-digital
> age came from the microphone.
>
> What was widely accepted as the "ideal" communications speech characteristic
> had a smooth rounded peak at 3kHz. Below 3 KHz it rolled off to about 10 dB
> down at 1 KHz and another 5 dB down at 200 Hz (with a steep drop below 200
> Hz). Above 3 KHz it rolled of smoothly to 10 dB down at 5 KHz and continued
> to drop to about 30 dB down at 10 KHz.
>
> Many high-end communications microphone companies tried very hard to match
> that characteristic in their products since nothing but general frequency
> shaping with capacitors was done in the rigs. Astatic was successful in
> doing that with the venerable D-104, which is why it was popular among Hams
> for many decades - and still has a strong following.
>
> Ron AC7AC
>
> -----Original Message-----
>
> On 11/19/2010 6:23 PM, Luis V. Romero wrote:
>> These Orions are really bassy.
>
> I understand. Makes you appreciate the K3 even more -- no need for the
> W2IHY unit, or for external EQ.
>
> Take a look at the simple circuit that Joe, W4TV, posted yesterday.
> It's a very old broadcast engineering technique that we both remembered.
> I've used the series capacitor when I wanted to use other pro mics with
> ham rigs that lacked mic EQ, and it worked quite well. You'll see that
> in the Ham Interfacing tutorial that I posted to my website several
> years ago. The cap is for LF rolloff, not DC blocking (which is not
> needed). The only trick is finding the small cap needed to fit inside
> the connector.
>
> 73, Jim K9YC
> ______________________________________________________________
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

py5eg

RES: Yamaha CM500

In reply to this post by AD4C2009

Hi Folks

I just got a pair of CM500 which came without any catalog and I would
kindly ask the following questions:

1) I tested on my K3 and the boom set is working fine
2) I noticed that the CM500 has more base and less high frequency
respond comparing with the heil.
3) Has someone tested for yaesu rigs? What are the results?

Thanks in advance

ATILANO DE OMS
PP5EG - PY5EG
ZW5B, PS2T, PT5T
ARAUCARIA DX GROUP
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ab2tc

Re: RES: Yamaha CM500

Hi,

I also bought a pair of these based on the recommendations on the reflector and also on the Yahoo group. I have not put it on the air yet as I was thoroughly disappointed with the headphones on receive. There seems to be a profound lack of highs compared to any other headphones I own including a pair of Heil and a pair of Koss. I also strongly dislike the fact that each earpiece has a wire coming out of it. I'll keep using my Heil proset until they break.

AB2TC - Knut

py5eg wrote

Hi Folks

I just got a pair of CM500 which came without any catalog and I would
kindly ask the following questions:

1) I tested on my K3 and the boom set is working fine
2) I noticed that the CM500 has more base and less high frequency
respond comparing with the heil.
3) Has someone tested for yaesu rigs? What are the results?

Thanks in advance

ATILANO DE OMS
PP5EG - PY5EG
ZW5B, PS2T, PT5T
ARAUCARIA DX GROUP
<snip>

Mark n2qt

unequal power output per tone in FSK

I know this has been discussed before and the fix is on "the list"
but after 24 hours of watching the watt meter bounce on the two
fsk tones, is the solution getting closer?

Mark n2qt
(using 5 pole filters which I understand accentuates this)

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py5eg

RES: RES: Yamaha CM500

In reply to this post by ab2tc

Hi Knut
Thanks for your comments.
Regards and HNY
Oms PY5EG

ATILANO DE OMS
PP5EG - PY5EG
ZW5B, PS2T, PT5T
ARAUCARIA DX GROUP
-----Mensagem original-----
De: [hidden email]
[mailto:[hidden email]] Em nome de ab2tc
Enviada em: segunda-feira, 10 de janeiro de 2011 12:43
Para: [hidden email]
Assunto: Re: [Elecraft] RES: Yamaha CM500

Hi,

I also bought a pair of these based on the recommendations on the
reflector
and also on the Yahoo group. I have not put it on the air yet as I was
thoroughly disappointed with the headphones on receive. There seems to
be a
profound lack of highs compared to any other headphones I own including
a
pair of Heil and a pair of Koss. I also strongly dislike the fact that
each
earpiece has a wire coming out of it. I'll keep using my Heil proset
until
they break.

AB2TC - Knut

py5eg wrote:

>
> Hi Folks
>
> I just got a pair of CM500 which came without any catalog and I would
> kindly ask the following questions:
>
> 1) I tested on my K3 and the boom set is working fine
> 2) I noticed that the CM500 has more base and less high frequency
> respond comparing with the heil.
> 3) Has someone tested for yaesu rigs? What are the results?
>
> Thanks in advance
>
> ATILANO DE OMS
> PP5EG - PY5EG
> ZW5B, PS2T, PT5T
> ARAUCARIA DX GROUP
> <snip>
>

--
View this message in context:
http://elecraft.365791.n2.nabble.com/Yamaha-CM500-tp5750572p5907129.html
Sent from the [HAM] mailing list archive at Nabble.com.
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Nr4c

Re: unequal power output per tone in FSK

In reply to this post by Mark n2qt

I may be all wet here, but I seem to think this is understandable.
FSK uses two tones, one is the MARK and one is SPACE. There are only
two states, you will have one or the other tones on the air all the
time. One tone is the base, and if the signal is un-modulated, it
would be transintted 100% of the time. The other tone is a pulsed
deviation from the base, so is only "ON" for short pulses when needed
to form a character. Since there is hardly ever an even distribution
of MARK/SPACE, the power out will not be the same.

My $.015 worth.

...bc nr4c

Quoting Mark n2qt <[hidden email]>:

> I know this has been discussed before and the fix is on "the list"
> but after 24 hours of watching the watt meter bounce on the two
> fsk tones, is the solution getting closer?
>
>
> Mark n2qt
> (using 5 pole filters which I understand accentuates this)
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
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>
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AD4C2009

Re: RES: Yamaha CM500

In reply to this post by ab2tc

Lack of highs? Not mine,besides,does any ham transmit today with more than 4000Hz at the high end? answer is NO,most of them are below 3000Hz,at that freq ANY headset will response well.Also I injected an audio generator to my CM-500 from 20 to 5000Hz and I heard the tone from 60(my ears) all the way up to 5000Hz with same level,I don't see why they has "lack of highs".Besides the K3 has an excellent RX EQ and you can tailor the received audio to your personal taste so If you think it has too much lows,then cut them up with it.
I have been using those Yamaha for more than a year and for me they sound as well as ANY other headset. Maybe some users feel bad because they are "cheap" compared with Heil, Senhisser,and others.

AD4C

"If freedom means something,it is the right to tell others what they don't want to hear" –George Orwell

--- On Mon, 1/10/11, ab2tc <[hidden email]> wrote:

From: ab2tc <[hidden email]>
Subject: Re: [Elecraft] RES: Yamaha CM500
To: [hidden email]
Date: Monday, January 10, 2011, 2:42 PM

Hi,

I also bought a pair of these based on the recommendations on the reflector
and also on the Yahoo group. I have not put it on the air yet as I was
thoroughly disappointed with the headphones on receive. There seems to be a
profound lack of highs compared to any other headphones I own including a
pair of Heil and a pair of Koss. I also strongly dislike the fact that each
earpiece has a wire coming out of it. I'll keep using my Heil proset until
they break.

AB2TC - Knut

py5eg wrote:

--
View this message in context: http://elecraft.365791.n2.nabble.com/Yamaha-CM500-tp5750572p5907129.html
Sent from the [HAM] mailing list archive at Nabble.com.
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py5eg

RES: RES: Yamaha CM500

Hi Hector
What about the microphone quality?
Did you also used it with Yaesu?
Thanks for the information
73
Oms

-----Mensagem original-----
De: [hidden email] [mailto:[hidden email]] Em nome de Hector Padron
Enviada em: segunda-feira, 10 de janeiro de 2011 17:40
Para: ab2tc
Cc: [hidden email]
Assunto: Re: [Elecraft] RES: Yamaha CM500

Lack of highs? Not mine,besides,does any ham transmit today with more than 4000Hz at the high end? answer is NO,most of them are below 3000Hz,at that freq ANY headset will response well.Also I injected an audio generator to my CM-500 from 20 to 5000Hz and I heard the tone from 60(my ears) all the way up to 5000Hz with same level,I don't see why they has "lack of highs".Besides the K3 has an excellent RX EQ and you can tailor the received audio to your personal taste so If you think it has too much lows,then cut them up with it.
I have been using those Yamaha for more than a year and for me they sound as well as ANY other headset. Maybe some users feel bad because they are "cheap" compared with Heil, Senhisser,and others.

AD4C

"If freedom means something,it is the right to tell others what they don't want to hear" -George Orwell

--- On Mon, 1/10/11, ab2tc <[hidden email]> wrote:

From: ab2tc <[hidden email]>
Subject: Re: [Elecraft] RES: Yamaha CM500
To: [hidden email]
Date: Monday, January 10, 2011, 2:42 PM

Hi,

I also bought a pair of these based on the recommendations on the reflector
and also on the Yahoo group. I have not put it on the air yet as I was
thoroughly disappointed with the headphones on receive. There seems to be a
profound lack of highs compared to any other headphones I own including a
pair of Heil and a pair of Koss. I also strongly dislike the fact that each
earpiece has a wire coming out of it. I'll keep using my Heil proset until
they break.

AB2TC - Knut

py5eg wrote:

--
View this message in context: http://elecraft.365791.n2.nabble.com/Yamaha-CM500-tp5750572p5907129.html
Sent from the [HAM] mailing list archive at Nabble.com.
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ab2tc

Re: RES: Yamaha CM500

In reply to this post by AD4C2009

Hello again,

I am not talking about anything above 2700Hz at all. With my receive bandpass set to 300-2700Hz the CM-500 sound definitely muffled compared to any other headphones I have. Yes, I could compensate with the EQ, but then it would be unuseable with any other headphones I have since there is no macro support to quickly change the RX EQ settings quickly. Until that happens the CM-500 stays shelved in my shack.

AB2TC - Knut

AD4C2009 wrote

Lack of highs? Not mine,besides,does any ham transmit today with more than 4000Hz at the high end? answer is NO,most of them are below 3000Hz,at that freq ANY headset will response well.Also I injected an audio generator to my CM-500 from 20 to 5000Hz and I heard the tone from 60(my ears) all the way up to 5000Hz with same level,I don't see why they has "lack of highs".Besides the K3 has an excellent RX EQ and you can tailor the received audio to your personal taste so If you think it has too much lows,then cut them up with it.
I have been using those Yamaha for more than a year and for me they sound as well as ANY other headset. Maybe some users feel bad because they are "cheap" compared with Heil, Senhisser,and others.

AD4C
<snip>

K5SM

Re: unequal power output per tone in FSK

In reply to this post by Mark n2qt

I also noticed this, and it was quite pronounced. In my case, the higher
output tone resulted in higher output than the pwr control setting. It
seemed the lower output tone produced the output the K3 was set for, but
the higher output tone was about 10% higher. I was operating FSK. When I
switched back to cw, output was normal (as set). I compensated by
reducing power setting accordingly, running about 75 watts during the
RU. As this was my first time to use the K3 in a RTTY contest, I was
monitoring everything very closely. Though the fan ran often, PA temp.
never got above 46c. Current varied with modulation as well.

Bob K5SM
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Hank Garretson

Re: unequal power output per tone in FSK

In reply to this post by Nr4c

Mark and space switch between two frequencies 170 Hz apart. There should be
no change in amplitude between mark and space.

With my K3 the difference between mark and space is about 1 dB. Too much.
Elecraft is aware of the problem, and the sooner it gets fixed the better.

Side note. There were some pretty wide RTTY signals in the Roundup. It
would be interesting for someone smarter than me to calculate the bandwidth
of a 0-dB-difference-between-mark-and-space signal and the bandwidth of a
1-dB-difference signal. I sure hope my signal wasn't one of the wide ones.

73,

Hank, W6SX

On Mon, Jan 10, 2011 at 8:54 AM, <[hidden email]> wrote:

I may be all wet here, but I seem to think this is understandable.
> FSK uses two tones, one is the MARK and one is SPACE. There are only
> two states, you will have one or the other tones on the air all the
> time. One tone is the base, and if the signal is un-modulated, it
> would be transintted 100% of the time. The other tone is a pulsed
> deviation from the base, so is only "ON" for short pulses when needed
> to form a character. Since there is hardly ever an even distribution
> of MARK/SPACE, the power out will not be the same.
>

Ski Exuberantly,

Hank

Mammoth Lakes, California

Elevation 8083 feet in John Muir's Range of Light
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wayne burdick

Re: unequal power output per tone in FSK

Administrator

Hi Hank,

The difference in amplitude is due to the small amount of ripple in
the crystal filter. The effect on transmission bandwidth is
negligible, and it's also extremely unlikely to affect copy.
Nonetheless, we're planning to provide a way to tune out the difference.

73,
Wayne
N6KR

On Jan 10, 2011, at 3:26 PM, Hank Garretson wrote:

> Mark and space switch between two frequencies 170 Hz apart. There
> should be
> no change in amplitude between mark and space.
>
> With my K3 the difference between mark and space is about 1 dB. Too
> much.
> Elecraft is aware of the problem, and the sooner it gets fixed the
> better.
>
> Side note. There were some pretty wide RTTY signals in the
> Roundup. It
> would be interesting for someone smarter than me to calculate the
> bandwidth
> of a 0-dB-difference-between-mark-and-space signal and the bandwidth
> of a
> 1-dB-difference signal. I sure hope my signal wasn't one of the
> wide ones.
>
> 73,
>
> Hank, W6SX
>
>
> On Mon, Jan 10, 2011 at 8:54 AM, <[hidden email]> wrote:
>
> I may be all wet here, but I seem to think this is understandable.
>> FSK uses two tones, one is the MARK and one is SPACE. There are only
>> two states, you will have one or the other tones on the air all the
>> time. One tone is the base, and if the signal is un-modulated, it
>> would be transintted 100% of the time. The other tone is a pulsed
>> deviation from the base, so is only "ON" for short pulses when needed
>> to form a character. Since there is hardly ever an even distribution
>> of MARK/SPACE, the power out will not be the same.
>>
>
>
>
>
>
> Ski Exuberantly,
>
> Hank
>
> Mammoth Lakes, California
>
> Elevation 8083 feet in John Muir's Range of Light
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Eric Swartz - WA6HHQ

Re: unequal power output per tone in FSK

Administrator

5 pole 2.7 kHz SSB filters will also have a little more natural ripple
than the 8 pole 2.8s.

73,
Eric

On 1/10/2011 3:35 PM, Wayne Burdick wrote:

> Hi Hank,
>
> The difference in amplitude is due to the small amount of ripple in
> the crystal filter. The effect on transmission bandwidth is
> negligible, and it's also extremely unlikely to affect copy.
> Nonetheless, we're planning to provide a way to tune out the difference.
>
> 73,
> Wayne
> N6KR

Kok Chen

Re: unequal power output per tone in FSK

In reply to this post by wayne burdick

On Jan 10, 2011, at 3:35 PM, Wayne Burdick wrote:

> The effect on transmission bandwidth is negligible, and it's also extremely unlikely to affect copy.

It depends.

Consider an RTTY demodulator that includes automatic threshold correction (ATC). It will treat such a signal as one with 1 dB worth of constant, selective fading. This will affect the SNR of the whole scheme. I.e., when you apply a threshold correction the noise goes up by the same amount. To boost the lowered tone, the noise in that channel is also boosted. You can see the effect exposed here

http://homepage.mac.com/chen/Technical/FSK/ATC/

So, unless you apply the more complex circuit (I don't know anyone else than myself who uses it), the character error rate will be affected by the amount that is equivalent to 1 dB more SNR degradation.

How much is it? With a weak but stable conditions (no fading, no flutter), a 1 dB imbalance can double the character error rate. If you have fluttery condition, it is true that 1 dB of degraded SNR won't do much additional harm.

You can apply the same analysis for "FM" demodulators and should see something similar. Some modems in the early days use hard limited "FM" demodulators instead of an ATC to fight selective fading because of the Page Communications patent 2,999,925.

Some of us RTTY nuts tweak for the last decibel :-).

73
Chen, W7AY

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Joe Subich, W4TV-4

Re: unequal power output per tone in FSK

In reply to this post by Eric Swartz - WA6HHQ

After properly performing the TX Gain calibrations, I don't
see any significant difference between tones (K3 s/n 477):

Mark Space Difference
at 100W 100.50 100.40 -0.004 dB
80W 80.70 79.50 -0.06 dB
60W 60.90 60.00 -0.06 dB
40W 40.50 39.70 -0.08 dB
20W 20.22 19.61 -0.13 dB

Measured into a known flat 50 Ohm dummy load with TelePost LP-100
watt meter. K3 is keyed in FSK, power at mark recorded and the FSK
line closed and power at Space tone recorded without opening PTT.
If PTT is opened and closed between reading power at Mark and Space,
the two power levels are identical within the resolution of the
watt meter.

73,

... Joe, W4TV

On 1/10/2011 7:07 PM, Eric Swartz - WA6HHQ, Elecraft wrote:

> 5 pole 2.7 kHz SSB filters will also have a little more natural ripple
> than the 8 pole 2.8s.
>
> 73,
> Eric
>
>
> On 1/10/2011 3:35 PM, Wayne Burdick wrote:
>> Hi Hank,
>>
>> The difference in amplitude is due to the small amount of ripple in
>> the crystal filter. The effect on transmission bandwidth is
>> negligible, and it's also extremely unlikely to affect copy.
>> Nonetheless, we're planning to provide a way to tune out the difference.
>>
>> 73,
>> Wayne
>> N6KR
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

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