PICS FIXED!. (finally) Saber 100% duty cycle

[ricciticcitembo]

Anybody else ever use a Saber for a continuous duty Transmitter
with a housing eliminator on a large slab of aluminum ?

I ran it yesterday with 2-3 Watts out for 17 Hours.

Can I go for 5-6 Watts?? Or would that be pushing my luck????

It got pretty warm yesterday in the full sunlight at low power......


EDITED 10-07-04
These are the old photos. The new ones are near the end of this thread.
I have changed the original photos as links instead of self displaying
in order to increase speed response time for the New ones which are much better.

original Becker unit photographs found here-
http://myte.sytes.net:8080/Mot/SaberPeter01.JPG
http://myte.sytes.net:8080/Mot/SaberPeter02.JPG
http://myte.sytes.net:8080/Mot/SaberPeter03.JPG

[Tom in D.C.]

Dave:

I think you're breaking new ground here, or something.

I was sitting on my side porch one evening recently for my nightly
QSO at 1900 with a friend up in Baltimore. Instead of my VX900 I
was using my Saber III. It's programmed for highest power on the
repeaters and it's an H44, so I guess it's putting out 6 watts.

By the time I had made about ten relatively short transmissions the
thing was really getting warm on the back, let me tell you. I know
it's probably designed to do that but it still makes me nervous.

My inexpert guess would be that the RF section on a Saber would
loaf along at 2 to 3 watts for a long, long time, just as you found
when you did your "test." High power, I don't know. Do you have a spare final amp module just in case?

Regards,

Tom in D.C.
W2NJS

[Tom in D.C.]

deleted by sender

[ricciticcitembo]

Thanks for the reality check, Tom. I'll just put an Amp on it.
What the hell was I thinking? I was up very late the night before.


And yes, actually I do happen to have a spare known good PA.
However thanks to your kind reminder, I won't be needing it any
time soon. I set it at 2.0 Amps Transmit current. No more getting
hot.

I'll feed that into a nice 35W HT amp, and get 10W all day long.

Thanks.

Dave.

[Dale Earnhardt]

Countious duty on a saber

I dont even do that to my AS3 lol or even close to 2 min

[ricciticcitembo]

Actually I'm hoping it will Transmit Forever like that.
And from all observations so far it will.

A few more facts for those that might try this:

-The Saber unit in question was the best one I had performance wise.

- I then removed it from it's case, dissasembled then reassembled
it VERY very carefully, Cutting and filing along the way and insuring
an excellent physical bond between
a brand new PA and the frame.
Lots of Dow Corning Silicone Heatsink compound was used also.

-Next I custom machined out of 3/4 Inch Aluminum Bar stock, A mount
for the side of the Saber with the PA on it

-This assembly was then mounted in
a Mercedes Benz Becker Chassis
Model number 754 Grand Prix
using the Stock Heatsink on the Left side For the Saber PA unit.

-The right side heatsink on the Becker 754 is connected to yet more
Aluminum inside with the custom
Powersupply I made for 10-24VDCin and 7.77 Volts out.

-A repeater controller and an AK16 DTMF controller was added with opto-
isolators and other stuff. Lots of
wires inside and db 25 connectors....

-The Saber is hardwired inside NO-case and after it passes the next test, the frontshield will be soldered on to the chassis, to knock out any stray RF if there is any.

-Finally one MX300 battery was installed in the chassis to facilitate Emergency operation.

-If I snap back on the Frontplate to the head unit, You can't even
tell it's been modified. It just looks exactly like a normal Benz
Radio.

I'll have to go over to my friend's
house and take a pic of it. It's
way slicker than the other repeater
I made, But alas this unit used to
house TWO Sabers but would not do
100% Duty, so I removed one unit and Fortified the remaining one.
Now I need to build one more of these and I'll have what I used to
have, except it's now twice the size but at least it's 100%.

In conclusion, The Saber is my favorite radio overall. I like Beckers too, but less so because they break.....
I haven't Broken ANY Sabers yet, and God knows I've tried real hard.
They are mighty good radios for sure.
I really don't think anybody will ever make a better Walkie Talkie.
Nobody has yet......The Suberb RF performance with the Submersible package is hard to beat.

[Will]

Does that work along with your Spectra mobile?

[ricciticcitembo]

Of course. You guessed it, It's working right now.

That Spectra you fixed is still in the briefcase repeater.
Darn that radio is good. Best one out of all of them, I'll never get
rid of it. I can Talk easily from Deleware to Pennsylvania on that radio.
Thats Amazing for UHF. The reception on that radio is awesome,
especially considering my favorite machine is 7 Mhz out of band.

Sometime I'd like to send you my 800. I think it might have some
leaky caps on the command board. Better to get it fixed before it
blows up. It hisses a little.... I gotta get another one first though,
I don't think I can live without it. Ever since one of our offices
caught on fire (it wasn't in our section of the building) and the alarm
went off, and I heard the dispatch and made it to the office before
the trucks did. Got the Server out of the building too.(unnecessarily)

[Keygun]

Anybody else ever use a Saber for a continuous duty Transmitter
with a housing eliminator on a large slab of aluminum ?

I ran it yesterday with 2-3 Watts out for 17 Hours.

Can I go for 5-6 Watts?? Or would that be pushing my luck????

It got pretty warm yesterday in the full sunlight at low power......

The problem is the relative small amount of metal inside the radios: only the housing of the PA-module itself and the thin frame. Not a good heatsink. So the PA-module rans rather warm even with low power levels. The PA modules with their ceramic substrates inside, are very rugged, but not indistructable. So even a 6 watt VHF-Saber is capable put out at least 8 Watt, i would not recommend it.

Keygun

[ricciticcitembo]

I like how I changed the stock anti-theft connector with a db15
for an extra Spectra to be connected for monitoring on the rear
panel of the Becker. It was a perfect fit.

[Cowthief]

Hello.

I found some portables that were hacked for 100% duty cycle when looking for wireless microphone replacements.
Some church member had taken a saber and added a stainless steel "patch". This did not stick out of the case, so my guess is that he cut the plastic housing. I would have loved to find out more, however someone said he was no longer around. I would love to see some ideas for 100% duty cycle portables, repeater or otherwise, for wireless mic use.

Thank You.

[ricciticcitembo]

I used my Standard C-508A as a wireless mic before in church.
All I did was tape the TX on with some electrical tape.
It is only a 200mw radio. And as far as I know there IS a Wireless
mic mod for the Saber, but it is low power also.

How long do you think an Extra High Capacity battery lasts
transmitting at 2-3 Watts?

Not long. Not long at all. You'd be lucky to get 30 Minutes out of it.

[Susan157]

Has anyone tried the transmitter in the WalMart
$43.00 six can 12 volt electric cooler.

or used the cooler unit (Throw Box Away)
and bolted it on to a mobile heat sink??

Just Thinking From Canada.
They use coolers on Computers.

[kf4sqb]

Good idea, Susan! Why didn't I think of that? I have , however, seen people put a "shell" around their radio(s) and run a duct from the air-conditioning system into the "shell".

[wa2zdy]

Good idea, Susan! Why didn't I think of that? I have , however, seen people put a "shell" around their radio(s) and run a duct from the air-conditioning system into the "shell".

I should have thought of that one myself. I used to have a ham transmitter (back in about 1976 or so) from the mid 50s and man did THAT thing cook! During the winter when I used it most, I had some flexible duct pipe (or whatever you'd call it) coming in from the window to the transmitter. With a nice fan it sucked cold outside air in and through the transmitter. During the summer, HF wasn't all that so I didn't run into many problems.

Good luck.

[ricciticcitembo]

OK. Here is my latest model Saber Repeater. There are two of these
units in operation.

[alex]

If you want, email me your photo's, and I'll host them and change your post. I tried to fix them for you, however, webshots is a PITA, and is probably looking for a refer in order to show you the images.

I think you have my address...

-Alex

[Lord Windeshmere]

Well, it should only be a short time before the whole thing goes on you, why with that Becker radio you're using only adding bad karma to the whole shebang! In all the Benz's I've owned I've never had a Becker radio last. Seriously, I wish you good luck with the setup. Pretty sweet.

[ricciticcitembo]

Deleted. Because I messed it up by accident. DOH.

[ricciticcitembo]

OK. Pictures Fixed.



And Also the other Saber Repeater Thread Pictures have been corrected.

They are the same pictures, but that's where all of the Text is.

http://batboard.batlabs.com/viewtopic.php?t=34329

And some final words.


Special Thanks and Credits to the Following people, who without
their support and direction , this project would not have been possible-

Jack Cobb, firemedic, 10-95 Frank, Alex, Monty, and Will.

THANKS GUYS!



Those Targa audio amplifiers are like 15-20 Years old already.
And I fully Expect this Saber Repeater Unit to last at least that long.

Dave