Has anyone ever removed an antenna tuner from a radio and...
 

This may not seem like a "homebrew" question, but it is!

I have a Kenwood 440SAT which is failing, but the AT (Antenna Tuner)
is still working. Since the 440SAT can (could) also be purchased as a
440S (i.e., without the AT), the AT may be a stand-alone "module", and
I'd like to remove it and package it separately to use with a new radio.

I also own a nice crossed-needle VSWR meter, so I don't have to depend
on the one in the 440.

Any suggestions?

--
--Myron A. Calhoun.
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
NRA Life Member & Certified Instructor for Rifle, Pistol, & Home Firearm Safety
Also Certified Instructor for the Kansas Concealed-Carry Handgun (CCH) license

Has anyone ever removed an antenna tuner from a radio and...
 

Has anyone ever removed an antenna tuner from a radio and...
 

gwatts wrote:
wrote:

This may not seem like a "homebrew" question, but it is!

I have a Kenwood 440SAT which is failing...

Any suggestions?


How is the 440SAT failing? Any chance of repairing it or selling it as-is?

W8LNA

To which I should have added:
Taking the tuner out of the radio and making it work as a stand-alone
tuner might be interesting but more likely a huge effort. You should
first get the manuals and schematics for the radio and the stand alone
Kenwood tuner and see what ends up where between the built-in and
stand-alone versions. If you can fix the radio then you have a radio
with a built-in tuner. If you sell the radio as-is you might have
enough to buy a new auto-tuner like an LDG,
http://www.ldgelectronics.com/ If you actually can remove the tuner and
make it work as a stand-alone version you should write an article about it.

Has anyone ever removed an antenna tuner from a radio and...
 

I don't see why it would be a big deal to remove the auto-tuner from the
440SAT. I have the 690S(AT) which is just a 450S with 6M built in. The
manual for the radio has a 9 step instruction for INSTALLING the
auto-tuner. Start at step 9 and work backwards to UN-install the tuner.
The 450 is basically an updated 440.

Scott
N0EDV

gwatts wrote:
gwatts wrote:

wrote:

This may not seem like a "homebrew" question, but it is!

I have a Kenwood 440SAT which is failing...

Any suggestions?



How is the 440SAT failing? Any chance of repairing it or selling it
as-is?

W8LNA


To which I should have added:
Taking the tuner out of the radio and making it work as a stand-alone
tuner might be interesting but more likely a huge effort. You should
first get the manuals and schematics for the radio and the stand alone
Kenwood tuner and see what ends up where between the built-in and
stand-alone versions. If you can fix the radio then you have a radio
with a built-in tuner. If you sell the radio as-is you might have
enough to buy a new auto-tuner like an LDG,
http://www.ldgelectronics.com/ If you actually can remove the tuner and
make it work as a stand-alone version you should write an article about it.

--
Scott
http://corbenflyer.tripod.com/
Gotta Fly or Gonna Die
Building RV-4 (Super Slow Build Version)

Has anyone ever removed an antenna tuner from a radio and...
 

"Scott" wrote in message
.. .
I don't see why it would be a big deal to remove the auto-tuner from the
440SAT. I have the 690S(AT) which is just a 450S with 6M built in. The
manual for the radio has a 9 step instruction for INSTALLING the
auto-tuner. Start at step 9 and work backwards to UN-install the tuner.
The 450 is basically an updated 440.

I expect it should be relatively easy to remove the tuner, *BUT*, OP wanted
to use the tuner after it was removed. Most modern radios have fairly
elaborate microcontrollers. An astute engineer would likely use the
existinc CPU for the autotuner, rather than adding another, unless the tuner
option were an afterthought.

Even if the tuner had a dedicated processor, the controls from the tuner
almost certainly come from the rig's main processor. I suspect it might be
fairly tricky figuring out how to talk to it, even if OP is a
microcontroller guru. In any case, he is likely looking at a significant
micro project to make it work.

...

Has anyone ever removed an antenna tuner from a radio and...
 

I have a Kenwood 440SAT which is failing.... Any suggestions?

How is the 440SAT failing? Any chance of repairing it or selling it as-is?

Ignoring the "bouncy" buttons, everything works fine on CW but won't
modulate. Microphone may have failed, and I haven't gotten around
to cobbling a substitute to the right connector.

FWIW, I realized today that I DO have full manuals and have learned that,
even though the AT can be an after-market addition, the schematics show
the AT is controlled by the radio's processor and making it work without
the radio will be a real pain!
--
--Myron A. Calhoun.
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
NRA Life Member & Certified Instructor for Rifle, Pistol, & Home Firearm Safety
Also Certified Instructor for the Kansas Concealed-Carry Handgun (CCH) license

Has anyone ever removed an antenna tuner from a radio and...
 

Oh...I didn't get what the original poster wanted to do...I thought he
wanted to use the radio without the tuner. So...yes, it might not be
the easiest thing to do (get the tuner working as a stand-alone unit).
Taking a quick look at the schematic for the auto-tuner in my 690, it
appears most of the brains are in the tuner itself. Unfortunately,
there are several signal inputs that are labeled cryptically, so it
might be a bit difficult to figure out what they are used for...

Scott
N0EDV

xpyttl wrote:
"Scott" wrote in message
.. .

I don't see why it would be a big deal to remove the auto-tuner from the
440SAT. I have the 690S(AT) which is just a 450S with 6M built in. The
manual for the radio has a 9 step instruction for INSTALLING the
auto-tuner. Start at step 9 and work backwards to UN-install the tuner.
The 450 is basically an updated 440.


I expect it should be relatively easy to remove the tuner, *BUT*, OP wanted
to use the tuner after it was removed. Most modern radios have fairly
elaborate microcontrollers. An astute engineer would likely use the
existinc CPU for the autotuner, rather than adding another, unless the tuner
option were an afterthought.

Even if the tuner had a dedicated processor, the controls from the tuner
almost certainly come from the rig's main processor. I suspect it might be
fairly tricky figuring out how to talk to it, even if OP is a
microcontroller guru. In any case, he is likely looking at a significant
micro project to make it work.

..



--
Scott
http://corbenflyer.tripod.com/
Gotta Fly or Gonna Die
Building RV-4 (Super Slow Build Version)

Has anyone ever removed an antenna tuner from a radio and...
 

wrote in message ...

FWIW, I realized today that I DO have full manuals and have learned that,
even though the AT can be an after-market addition, the schematics show
the AT is controlled by the radio's processor and making it work without
the radio will be a real pain!

Actually, maybe not as much of a pain as if the thing had its own processor.
If the AT had a dedicated processor, there would certainly be some control
lines from the rig's processor. Reverse engineering what those control
lines did could be a real problem.

But if the AT is controlled by the rig's processor, then there are interface
lines to the things that need to be twiddled, and it should be fairly
obvious from the schematic what twiddles what. So the problem simply
becomes writing autotuner software, which isn't all that bad. All the grody
hardware work has been done for you! Ok, certainly not a trivial project,
but I'm not sure it rises to the level of "a real pain"

Of course, some folks have a different comfort level with a soldering iron
than with a keyboard, so I imagine there are some that might see it
differently.

...

Has anyone ever removed an antenna tuner from a radio and...
 

Agreed! I know which end of the solder stick to grab and I used to do
machine language programming for fun ;) I, no doubt, am one SICK SOB ;)

Scott
N0EDV

xpyttl wrote:


Of course, some folks have a different comfort level with a soldering iron
than with a keyboard, so I imagine there are some that might see it
differently.

..



--
Scott
http://corbenflyer.tripod.com/
Gotta Fly or Gonna Die
Building RV-4 (Super Slow Build Version)

Has anyone ever removed an antenna tuner from a radio and...
 

On Sep 26, 12:14 am, wrote:
This may not seem like a "homebrew" question, but it is!

I have a Kenwood 440SAT which is failing, but the AT (Antenna Tuner)
is still working. Since the 440SAT can (could) also be purchased as a
440S (i.e., without the AT), the AT may be a stand-alone "module", and
I'd like to remove it and package it separately to use with a new radio.


It would be a lot of work, for a somewhat mediocre result....and
speaking from working on the ATU in several TS440, here goes...

The tuner band switching is done via the radios CPU - could be hard
wired via a switch. But that sort of defeats the concept of an auto
ATU - still, amateurs have done weirder things than that before...

The SWR/tuning sensing is inside the ATU, no probs there...it does
feed back to the PA as a high SWR protector, how to use it would
require some thinking...

BUT the thing has a fairly limited tuning range anyway - its small,
has to fit inside the radio, so its ability to match to a wide range
is not very good (cant remember the figures)

Why not just fix the radio? - they go fine, have very little
commercial value so ideal mobile/backup radio - no great loss if its
stolen out of a vehicle. The Kenwood manual is excellent, easy to read
to fault find, and there is even a YAHOO group devoted to the beast...

73 de VK3BFA Andrew.