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ANY AMATEURS IN THE GROUP EVER RAN OR HAVE EXPERIENCE WITH THE RM HLA 300

TonyV225

TonyV225

W9WDX Amateur Radio Club Member
Apr 18, 2005
5,824
323
143
Wisconsin
I was looking at getting an Ameritron ALS-500 for mobile use but have been looking at these for over a year now on and off but I would like to find someone with experience with these or some who knows a little about them I know the Ameritron is a better choice but if these are ok I would consider this for mobile use.

Knights Electrocom
 

If they can provide the FCC Certification Documents to show that this amplifier has met US requirements per 97.315 of the rules, I might consider looking at it. Looks nice and sleek, and the advertising writers use many of the "feelgood" terms. If it's really this good, there's no reason not to get it Certified. They'd sell millions of them!

On the other hand ...
 
I was also thinking about the fact that they are not FCC approved like this Palomar TX 5200 I have herewhich also has the band selection/filtering right on front. Its kind of crazy these maufactures will go the extra mile and ad that filtering and not get them certified. :confused:
 
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Several things about this amplifier and amplifiers in general.
That FCC certification isn't exactly the fastest, cheapest thing in the world. It takes time, and they don't do it for free. If you are serious about getting into the business, that certification is a very nice thing to have. It's also sort of limiting because 'they' tend to watch you to make certain you do things 'right'. If you have no problem with doing things right, big deal. If there are any sort of 'shady' thingys you like doing, you may not think it's worth the effort.
This particular amplifier is an import. That complicates things a lot, especially with that certification thingy. No idea what the cost of something like that process is, but you can bet it isn't free.
Strictly from the 'legal' and practical ham point of view, and since almost all HF radios are around 100 watt output anyway, it typically means that you have to reduce power to use one of these thingys. Not all that difficult to do, but for only doubling your signal's effective "hear me" power? Is it really worth the effort? I don't know, what do you think?
(And while I didn't pay any attention to the price of those amplifiers, if it's in pounds, or euros, figure on tripling it for dollars. That nasty 'cost' thingy!)
They wouldn't be worth it to me, but that's just an opinion, like something else that everyone has...
- 'Doc
 
Max input power on that amp is 20 watts SSB. I bet it doens't have any type of input overload protection, either. I think it's also RF keyed, which means it will never get certified in the U.S.

If it's a good quality amp, I don't really care if it's FCC certified or not. At Dayton I talked to the President of Tokyo Hi-Power and he said they have a hard time getting their stuff certified, and that stuff is top quality! Even HRO sells Tokyo Hi-Power now.

Personally, on this RM Italty amp, I think I would rather spend a little bit more (it's not that much more) and get the Ameritron. The company is based in the U.S. and repairs their products. Who are you going to send that RM Italy amp to if you can't fix it your yourself?
 
They are close in price thats forsurewell I believe this amp in particular is over $400.00 so if looking at new the RM Italy is about half the price I was looking at the used side of the limits on input of the amplifier which is a simple task just getting into that particular menu setting on my new radios and adjustments on the older ones.

I love my Ameritrons but thought if these RM Italy amplifiers worked ok and had just a 100 watt difference in power output that is not a big deal however as mole stated when a repair may be needed that could be a huge problem.
 
the rm hla and sommerkamp amps are cb amps with extras,
the basic amp is a rmkl500 with larger wattage feedback resistors, they dont have proper lcr feedback circuits to flatten gain over the hf band so drive must be reduced to keep the same output as you move down in frequency,
they are supposed to have overdrive protection and do have vswr protection,
the biasing is unregulated,

since i had to fix one for a local ham friend id say the overdrive protection dont work so well,
they can also be prone to self oscillation at certain drive levels and certain frequencies tested into a good dummyload,

a cb amp in ham clothing;)
 
I know an amateur who runs one of the HLA-300 on 75 meters mobile, seems to work ok, but I've never see what the ouput looks like on a spectrum analyzer. If you are going to buy, I would stick with a true amateur amplifier. I have read reports that the ALS-500 will not do 500 watts as advertised, most say around 400 watts +/- is all they seem to get.

If you can swing it, the SGC power cube has gotten good reviews, although some say it is a little over protective, it will shut down, and go into protection mode quite a bit.

Other amps to consider, if you can find a good used unit is the Metron 1000B or a Ten Tec Hercules II, however both have parts that are hard to come by if you have a failure.

If you have the skills, you can also build a mobile amplifier. There are sources on the net that sell the boards, plans, combiners, filters, etc, that you need to assemble a mobile amplifier, but after it is all said and done, you will probably have close to what it costs to buy the Ameritron in a home brew, but with six transistors instead of four, which will give you a true 500 watts, but it will run a little cooler.

73
 
I should really pull out the Palomar TX 5200 I have in the closet here and try that thing once. It has the band selector and sports 4/2SC22290 which also should be good for 300-400 watts out but I havent talked to anyone who has actually ran one of these on the amateur bands and if Ill have to mess with the biasing or tuning of the input of the amp to work the other bands.
 
TonyV225 said:
I should really pull out the Palomar TX 5200 I have in the closet here and try that thing once. It has the band selector and sports 4/2SC22290 which also should be good for 300-400 watts out but I havent talked to anyone who has actually ran one of these on the amateur bands and if Ill have to mess with the biasing or tuning of the input of the amp to work the other bands.
Click to expand...

If you are going to try and run the Palomar, I suggest using a good wideband receiver and check the first three harmonic frequencies when you transmit to ensure that you do not have any spurs. If nothing shows, you might be okay, and don't tell anyone what you are running, no need to give any rule fanatics reason to give you a hard time about the amplifier. Just tell them you have a good antenna on the mobile.
 
The RM HLA300 plus is a very good amplfier. I worked on Motorola radios for over 40 years. When I saw the original 500 amplifier used Motorola transistors. I was impressed.
It was a 60 watt transistor for class c. For AM this would be about 240 watts. The 501
amplifiers are 1446 are 70 watt transistors. The HLA300vplus will do about 500 watts ssb before the filters or on 10-12 meters. It will filter anything above 50 mhz. If you have
equipment to check harmonics you can run 500 watts. If you use the filters for 40 or 80
meters you will have 400 watts. I use a MFJ 75 amp power supply set for 14.5 volts. If
you use 12 volts or 13.8 volts it will not put out as much. I run 20 - 25 watts in. It does
have input protection and swr protection but if you put 100 watts in you will probably
damage it. I dont think they will ever use 2879 100 watt transistors because it takes a
lot more drive. The Ameritron amp uses these transistors. If you look on Eham you will
find some people have no trouble with the Ameritron 500 but others have nothing but
trouble with it being returned DOA. The Ameritron is about $300 more. I know RM Italy
makes alot of stuff for cbers but I dont think they would pay $200 more for ham filters.
I have a home made amplifier with a home made filters, but forget to switch bands and
have damaged it more than once. The RM Italy has auto switching and I like it a whole lot.

Don Johnson KC6SPU
 
RM HLA-150 test

hla300v

I know several op's that run the 300v mobile, and work well.
I chat with a op from MI., that uses his every morning on 75...only issue he had was the attenuator circuit (cheap fix)....
Another op retrofitted his with 2879's and works very nice...shows maybe 100 watts more than stock, and is very clean on the spectrum analyzer.
I've got one here on the self, just have not done anything with it yet...other than tested for output.(only got $225 in mine)
I hope to run it in the truck if I ever get my screwdriver mounted this spring...:blink:
All the Best
BJ
 

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