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HLA 300V PLUS 1.8mhz and up. Is this any good?


I don't think it will work on 11 meters. The automatic band switching won't allow it. But I could be wrong.
That's a lot of money for an amp you want to use on cb. Way more complicated the KL-500 as the schematics will attest.
 

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I don't think it will work on 11 meters. The automatic band switching won't allow it. But I could be wrong.
That's a lot of money for an amp you want to use on cb.
I have been hitting the books, ope to test by X mass. What I was thinking was this being a "real" amp with filters and all it may not be a splatter box....and I have a bad habit of buying things "I may need..." if the price is right.
 
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Drive any cb amp according to manufacture specs of the transistor not the builder and you shouldn't need a filter
 
I have re pilled a couple of 300's & a 150,
At the heart of the hla300 is a kl500 with bigger resistors band pass filters & vswr protection on a bigger heatsink, its a cb amp with extras,

a few locals use hla300's & hla150's ( kl400 with extras ) on 27mhz.
 
Seems like a strange size amp for most ham rigs, but I could be wrong. It doesn't seem like a qrp rig would drive it very hard at all, and a lot of extra cost for little gain. Seems like a total waste on a 100 watt rig.

Cost wise, you are half way to paying for a used legal limit amp.
 
I have been hitting the books, ope to test by X mass. What I was thinking was this being a "real" amp with filters and all it may not be a splatter box....and I have a bad habit of buying things "I may need..." if the price is right.
It is a good amp for ham and as long as you don't over modulate or overdrive it will work good. It has plenty of filters and matching circuits and it is a pretty good design with the exception of the MS1051 transistors. All of the scope traces in my album are from testing MS1051 transistors. The quality of those transistors is fairly poor which is why so many amps failed. Defective transistors installed from the beginning.
3353-1425595712-c9dcca6d523e231d055dc9a40bc2a83f.jpg
 
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w8ji's test of the HLA150 showed that ignoring RM's mickeymouse output claims & keeping drive to sensible levels they are not so bad,
anything more than about 100w for the 2 transistor version causes too much IMD,

https://www.w8ji.com/rm_hla-150_test.htm

i would expect the hla300 to be a little less than double the hla150's output with combiner losses,

a qrp rig ft817 ft301 icom 703etc will drive the versions with sd1446's to that sort of output and more at lower frequencies where gain is higher,

i have never seen good results or maybe its lower gain from the handfull of RM's i have come across using ms1051's,
the larger & higher rated transistors seem to not work so well as a drop in replacement in that circuit.
 
If you change from the MS-1051 you need to re-bias the output transistors. When you replace any matched pair transistors you need to re-bias for balanced performance. If you don't you could possibly smoke a bunch of transistors just by turning it on.

w8ji's test of the HLA150 showed that ignoring RM's mickeymouse output claims & keeping drive to sensible levels they are not so bad,
anything more than about 100w for the 2 transistor version causes too much IMD,

https://www.w8ji.com/rm_hla-150_test.htm

i would expect the hla300 to be a little less than double the hla150's output with combiner losses,

a qrp rig ft817 ft301 icom 703etc will drive the versions with sd1446's to that sort of output and more at lower frequencies where gain is higher,

i have never seen good results or maybe its lower gain from the handfull of RM's i have come across using ms1051's,
the larger & higher rated transistors seem to not work so well as a drop in replacement in that circuit.
 
flame suit on...

Lets be honest here, this amp is clearly aimed at the CB community, the manuf calls it an (wink,wink nudge, nudge) Amateur amp, but the IMD data is for F3E mode only.

How much F3E operation do you do on 80 meters?

Sooooo,here we are in this thread and the (quite correct) comment was made about it being a "waste" to drive it to its rated output with a reduced output from a 100 watt Amateur radio on SSB.

Well,............... DUH!!!! thats' because it is just another junque CB amp.

flame suit off

At correct input drive levels, it would be an acceptable CW amp.

BTW: if you shop around, you can match that E-bay selling price and get one from a real "brick and mortar" business with a warranty backed by the seller.
 
Lets be honest here, this amp is clearly aimed at the CB community, the manuf calls it an (wink,wink nudge, nudge) Amateur amp, but the IMD data is for F3E mode only.

Well,............... DUH!!!! thats' because it is just another junque CB amp..

If you had looked inside of one of these amps you would know it is not a CB amp at all.
They have the KL-300 for CB amps.
There is a PLA chip that controls the out put band in which the linear transmits through.
Granted it is a waste if you have ICOM-746 or similar out put radio. There many relays, toroid's and capacitors used to match to the band and antenna you are using. I have one here that I have never used and doubt I ever will.
(PLA CHIP is a programmable logic array used for complex logic task)

With all of that said you are right about it being a junker of an amp. Just not right about the CB part.
 
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I have re pilled a couple of 300's & a 150,
At the heart of the hla300 is a kl500 with bigger resistors band pass filters & vswr protection on a bigger heatsink, its a cb amp with extras,

a few locals use hla300's & hla150's ( kl400 with extras ) on 27mhz.
Thank you for the help. I will not be getting this amp.
 

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