Large Linear ...

[TIN_CAN]

How do you tell which one you have?

I have the JD200, look at the label as shown in picture, I bought this for $70 canadian when they were cheap, I am in the midst of putting it in a spare project box I had.

 

[999]

This is mine. I guess it's a 3015?

 

[w9cll]

Do you know what 1600W gives you over 800W? A single S point on a CB S meter, that's it. But what it does give you is a whole load of headache and grief from lots and lots of common-mode RFI given the way your typical CBer installs antennas and does a piss poor job of RF grounding. If they can't even get it right for 20W what hope have they for doing it with 1600W?

Amen!

 

[Shockwave]

Do you know what 1600W gives you over 800W? A single S point on a CB S meter, that's it.

I only wish doubling your power could give you an S unit of signal increase. The truth is it only gives you 3db and that is equal to half of an S unit.

 

[Tokin]

One s unit or even 1/2 may be the difference between being heard and not.
This is where im going to buy the supply for my 1600dx 2879C amp.
https://www.parallelminer.com/product-category/power-supply-kit/page/2/

 

[Shockwave]

Since only one transistor in each bank of two is drawing current at any given time, 8 real 2SC2879's should never draw more than 100 amps. At that point, they are supporting the maximum safe collector current of 25 amps. Anything more is dangerously over driving the amplifier. This is why more power, eventually requires more volts with reduced drive to keep the current at 25 amps per bank.

 

[w9cll]

One s unit or even 1/2 may be the difference between being heard and not.

But is it worth the cost and effort?

 

[Slowmover]

But is it worth the cost and effort?

If I can fit three more alternators under the hood, right?

 

[Shockwave]

But is it worth the cost and effort?

You know the answer is no. You'll never see a situation where a broadcast station sees a need to increase signal and only files for a 3db increase because you simply do not achieve the goal with this small of a change. If someone is not willing to grab 6db, I would recommend they save the money until they are.

As a rule of thumb, if you want to really make a difference in signal, plan on having to add 10db to what is there now. That almost never happens by replacing one amplifier with another, unless a triode is being replaced with a much bigger tetrode. It usually requires using the existing amplifier, to drive a much larger additional stage.

PS: Think about the last time you saw someone replace a 5 transistor amp with a 10 transistor amp and were really impressed with their signal increase? Now think about the person that kept the "5 pill" and added 16 more behind it... When they go from just the driver to all 21 transistors, that 12db more is a world of difference.

 

[ForestRunner98]

Jeez adding a 100w amp with 2nd harmonics was hard enough to dial in!! LOL

 

[Tokin]

But is it worth the cost and effort?

That depends on the user

 

[TIN_CAN]

This is mine. I guess it's a 3015?View attachment 41030

Yet upper model number is the same....beats me.

 

[w9cll]

That depends on the user

yes I agree

 

[543_Dallas]

It definitely depends on the user. I'll take every fraction of an S unit I can get. I enjoy the work that goes into it more than actually talking on the radio. If I go to a bigger amplifier with the same gain I may not gain any output, but the improvement in IMD is worth it to me. I have an 8877 in my ham amp and am still building a 3cx3000. That tube has less gain but the build is part of the fun. It's also rewarding when you talk about equipment with someone and have more to talk about that walking into HRO and buying it. Repurposing server power supplies is a fine example of that.