Topics

Power supply voltage

Larry
 

Well the discussion just came to a halt it appears.  This kind of
reminded me of groups, new hams i

interfaced with back in the 70's.  There was this thing about SWR,
remember those days.  You gotta

have low swr or your going to hurt the radio.  To an extent that could
be true, but it was an over

correction.

In the 50's i used a DX-40 and an end fed wire to get on the air.  Since
i lived with my grandparents

i kinda had to do as they suggested.  SWR, What SWR?   Hey i can tune up
and work some guys on

cw so it must be working.  Then in the 70's SWR's was discovered.  You
gotta have low swr's and

the way to get them is to use an antenna noise bridge.  Remember them,
still got one here in the

shack.  Hams wouldn't operate more than a few kc from where they tuned
up cause SWR's would

be way off and, well you just don't know.  That lasted for a couple
years and then we went on to

something else.

Now we are at the point where my factory made and engineered radio is
impure,  if i operate at

any  power level other than 35 w, i'll not have optimum DBc in the noise
department.  So my

question was the other day, should i operate my K3, greatly upgraded, at
the 35W level on the

digital modes so i have the utmost cleanest DBc noise, where ever it is
located, or should i just

say the hell with it and go on operating like i have been and not worry
about this new disastrous

discovery that has been thrust upon us?  Who is going to know if i have
-35DBc noise or -29Dbc

noise on my signal?

You gotta be kidding.  Hey mom, i want to see that 35 calories you said
i shouldn't be eating,

yeah, put'em right here in my sweaty little palm.  I'll take some of
them DBc things as well.

Larry

W0OGH

Rob Sherwood
 

It appears that with WSJT X, aside from the DX end of fox/hound, IMD for the most part is a non-issue for FT8. If you need 100 watts to make the contact, go for it.

If you linear amp only needs 35 watts of drive, then you are at a sweet spot on SSB, assuming you amp is relatively clean. That would likely be true for a tube linear amp, but not a good assumption with a solid-state linear. In the case of the K3 at 35 watts, the rig would be about 6 dB cleaner than virtually any solid-state amp. This is a generalization since all this varies from band to band.

Enjoy you time on the air, and be a good neighbor as best you can. We all have to share our spectrum.

Rob, NC0B

-----Original Message-----
From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Larry
Sent: Friday, November 08, 2019 4:35 PM
To: Elecraft-K3@Groups.io
Subject: [Elecraft-K3] Power supply voltage

Well the discussion just came to a halt it appears.  This kind of
reminded me of groups, new hams i

interfaced with back in the 70's.  There was this thing about SWR,
remember those days.  You gotta

have low swr or your going to hurt the radio.  To an extent that could
be true, but it was an over

correction.

In the 50's i used a DX-40 and an end fed wire to get on the air.  Since
i lived with my grandparents

i kinda had to do as they suggested.  SWR, What SWR?   Hey i can tune up
and work some guys on

cw so it must be working.  Then in the 70's SWR's was discovered.  You
gotta have low swr's and

the way to get them is to use an antenna noise bridge.  Remember them,
still got one here in the

shack.  Hams wouldn't operate more than a few kc from where they tuned
up cause SWR's would

be way off and, well you just don't know.  That lasted for a couple
years and then we went on to

something else.

Now we are at the point where my factory made and engineered radio is
impure,  if i operate at

any  power level other than 35 w, i'll not have optimum DBc in the noise
department.  So my

question was the other day, should i operate my K3, greatly upgraded, at
the 35W level on the

digital modes so i have the utmost cleanest DBc noise, where ever it is
located, or should i just

say the hell with it and go on operating like i have been and not worry
about this new disastrous

discovery that has been thrust upon us?  Who is going to know if i have
-35DBc noise or -29Dbc

noise on my signal?

You gotta be kidding.  Hey mom, i want to see that 35 calories you said
i shouldn't be eating,

yeah, put'em right here in my sweaty little palm.  I'll take some of
them DBc things as well.

Larry

W0OGH

Dan Abell
 

I for one have learned from this discussion, along with Rob’s QST article. While many hams can care less, at least we, and manufactures hopefully, are more aware of the issues on the transmit side.

I would agree, however this thread is well beyond the K3 domain, however I’d like to think that Elecraft owners embrace the wider discussion more than most. Thanks to all who have made a material contribution to the topic.
Dan W3dka

On Nov 8, 2019, at 22:50, Rob Sherwood <rob@...> wrote:

It appears that with WSJT X, aside from the DX end of fox/hound, IMD for the most part is a non-issue for FT8. If you need 100 watts to make the contact, go for it.

If you linear amp only needs 35 watts of drive, then you are at a sweet spot on SSB, assuming you amp is relatively clean. That would likely be true for a tube linear amp, but not a good assumption with a solid-state linear. In the case of the K3 at 35 watts, the rig would be about 6 dB cleaner than virtually any solid-state amp. This is a generalization since all this varies from band to band.

Enjoy you time on the air, and be a good neighbor as best you can. We all have to share our spectrum.

Rob, NC0B

-----Original Message-----
From: Elecraft-K3@groups.io [mailto:Elecraft-K3@groups.io] On Behalf Of Larry
Sent: Friday, November 08, 2019 4:35 PM
To: Elecraft-K3@Groups.io
Subject: [Elecraft-K3] Power supply voltage

Well the discussion just came to a halt it appears. This kind of
reminded me of groups, new hams i

interfaced with back in the 70's. There was this thing about SWR,
remember those days. You gotta

have low swr or your going to hurt the radio. To an extent that could
be true, but it was an over

correction.

In the 50's i used a DX-40 and an end fed wire to get on the air. Since
i lived with my grandparents

i kinda had to do as they suggested. SWR, What SWR? Hey i can tune up
and work some guys on

cw so it must be working. Then in the 70's SWR's was discovered. You
gotta have low swr's and

the way to get them is to use an antenna noise bridge. Remember them,
still got one here in the

shack. Hams wouldn't operate more than a few kc from where they tuned
up cause SWR's would

be way off and, well you just don't know. That lasted for a couple
years and then we went on to

something else.

Now we are at the point where my factory made and engineered radio is
impure, if i operate at

any power level other than 35 w, i'll not have optimum DBc in the noise
department. So my

question was the other day, should i operate my K3, greatly upgraded, at
the 35W level on the

digital modes so i have the utmost cleanest DBc noise, where ever it is
located, or should i just

say the hell with it and go on operating like i have been and not worry
about this new disastrous

discovery that has been thrust upon us? Who is going to know if i have
-35DBc noise or -29Dbc

noise on my signal?

You gotta be kidding. Hey mom, i want to see that 35 calories you said
i shouldn't be eating,

yeah, put'em right here in my sweaty little palm. I'll take some of
them DBc things as well.

Larry

W0OGH