Tube Amp adjustment.

[silver devil]

here is the info you need for your amp. Unfortunately there are only pictures on that website. It is made by SOS Electronics RF Amplifiers.
The Scout 20 and mini Scout are the model names.
http://www.cbtricks.com/Amp/sos_electronics/index.htm

I'll bet that NOMAD has a schematic!

Didn't they also make a super scout too? I remember hearing that name in the early 1990s around my area from the old guys.

 

[silver devil]

Don't drive those amps with a high power radio. 2 or 3 am and about 10 to 12 on Dan is about it

 

[N8RMS]

ok so i see 2 of those old ones connected together in 4 spots, so you are saying take out the 2 old ones in each spot and just put one of those 1N5408 ? so i need to buy 4 of the new ones right, thank you much for your expert help, i am lost on this

 

[N8RMS]

Rock on!

The calibrated eyeball strikes again!

I would replace all eight rectifier diodes with type 1N5408. It's a 3-Amp 1000-Volt part. Eight of them are only slight overkill. The "170" number should mean that the original diodes were rated for 2.5 Amps.

They're cheap enough I wouldn't consider replacing "just two", or using one smaller than the 1N5408. It's a more-rugged part than the originals.

Good catch!

73

http://www.ebay.com/itm/10-Pack-1N5...216441?hash=item1ec346ceb9:g:bfsAAOSwax5YxuUw

wow 1.98 thats cheap

 

[N8RMS]

Didn't they also make a super scout too? I remember hearing that name in the early 1990s around my area from the old guys.

yes they did it was a 4 tube driving 8

i bought one couple years ago it arrived doa , guy refunded my money wish it would have worked, i would like to find a D&A 10 tube that works good

 

[N8RMS]

yes they did it was a 4 tube driving 8

i bought one couple years ago it arrived doa , guy refunded my money wish it would have worked, i would like to find a D&A 10 tube that works good

i would love to find a D&A warrior it has 4 driving 12 !!! !!! http://www.cbtricks.com/Amp/d_and_a/warrior/index.htm

 

[kopcicle]

i would love to find a D&A warrior it has 4 driving 12 !!! !!! http://www.cbtricks.com/Amp/d_and_a/warrior/index.htm

Umm , auuuh,
Last I checked a 6KV6 was over $25 and the whole 6MJ6/6LF6/6KG6/ anything was nearly $40 ea
$500 in tubes ? !

Single 3-500Z ...
Just do it .
If 3KV , hollow state, and the associated circuitry is too much for you then $500 will buy a decent solid state amplifier.
If you just have to sweep ...
https://pa0fri.home.xs4all.nl/Lineairs/Frinear400/frinear400eng.htm
And get an engineering lesson with it .

In the interest of full disclosure I still own a home brew
2 x 6KV6A + 4 x 6MJ6 10/11m space heater. I just don't recommend it for anyone without a masochistic makeup. 1000v on anything like the 6LQ6/6MJ6 is difficult to tame with just 4 tubes let alone 6 .

 

[N8RMS]

Umm , auuuh,
Last I checked a 6KV6 was over $25 and the whole 6MJ6/6LF6/6KG6/ anything was nearly $40 ea
$500 in tubes ? !

Single 3-500Z ...
Just do it .
If 3KV , hollow state, and the associated circuitry is too much for you then $500 will buy a decent solid state amplifier.
If you just have to sweep ...
https://pa0fri.home.xs4all.nl/Lineairs/Frinear400/frinear400eng.htm
And get an engineering lesson with it .

In the interest of full disclosure I still own a home brew
2 x 6KV6A + 4 x 6MJ6 10/11m space heater. I just don't recommend it for anyone without a masochistic makeup. 1000v on anything like the 6LQ6/6MJ6 is difficult to tame with just 4 tubes let alone 6 .

ya you have a point there, the new 2x8 transister hg2879 is 1300 bucks and does 2500 watts if you drive it hard, but run 1500 watts easy all day all night on legal amatuer bands

 

[BJ radionut]

Nomad: take a good look at the tuning caps picture...maybe the picture is messing with my old eyes, but to me the rotor plates look nowhere near centered. They appear to be touching the stater on every plate...Either way that air gap in pretty small...something just not right. I have seen those kind of caps shift with age due to loss in spring tension or just flat shift...trouble either way.
Anyone else see this?
All the Best
Gary

 

[nomadradio]

ok so i see 2 of those old ones connected together in 4 spots, so you are saying take out the 2 old ones in each spot and just put one of those 1N5408 ? so i need to buy 4 of the new ones right, thank you much for your expert help, i am lost on this

Each pair of rectifier diodes wired end-to-end are called a series pair. This boosts the voltage rating, and gives you the equivalent of four 2000-Volt diodes.

The full-wave bridge rectifier circuit uses four "diodes", but in this case each of those four is a series pair of two.

Just copy the layout using eight of the new diodes.

Oh, and BJ, I assumed that the camera creates an illusion of skewed capacitor plates. If they touch while tuning it, he'll know.

73

 

[N8RMS]

Nomad: take a good look at the tuning caps picture...maybe the picture is messing with my old eyes, but to me the rotor plates look nowhere near centered. They appear to be touching the stater on every plate...Either way that air gap in pretty small...something just not right. I have seen those kind of caps shift with age due to loss in spring tension or just flat shift...trouble either way.
Anyone else see this?
All the Best
Gary

 

[Captain Kilowatt]

Oh, and BJ, I assumed that the camera creates an illusion of skewed capacitor plates. If they touch while tuning it, he'll know.

73

Been there done that. I have the capacitor with the destroyed plates to prove it. It WAS a nice Johnson capacitor but not any more. 2400 volts and a 1Kw carrier.....man I miss those days in broadcasting. Some days you never knew IF you were coming back home or not.

 

[silver devil]

i would love to find a D&A warrior it has 4 driving 12 !!! !!! http://www.cbtricks.com/Amp/d_and_a/warrior/index.htm

I had one once but it was modified and someone took out four of the tubes and rewired it to use 31lq6 tubes. It never worked right so I sold it for parts. I still have the tubes. I kept them.

 

[nomadradio]

The Warrior had a lot of flaws, some of them fatal.

I think of as a case of "Too much of a good thing".

They worked best with the four baldie-tube "pre" driver bypassed, treating it as a 12-tube Phantom with a bigger power supply.

Getting one to work was one level of accomplishment. Keeping it running was more like riding a bucking bronco. "Can he go the full eight seconds?"

73

 

[N8RMS]

The Warrior had a lot of flaws, some of them fatal.

I think of as a case of "Too much of a good thing".

They worked best with the four baldie-tube "pre" driver bypassed, treating it as a 12-tube Phantom with a bigger power supply.

Getting one to work was one level of accomplishment. Keeping it running was more like riding a bucking bronco. "Can he go the full eight seconds?"

73

i love how you put things in realistic perspectives, i am waiting on my diodes and going to test the tubes this week , so with the diodes broke on that one side is that dumping the power into a ground and bogging it down ? just trying to understand the purpose of the diodes and what happens when they broke or not there, is there anything else i need to inspect again close ? thanks so much for your help you are a life saver