Italian food is great but their mobile amps are junk. You get exactly what you pay for.
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Italian linear?
- Thread starter Pman62
- Start date
I have 4 of the RM Italy KL-200P Amps and one is over 20 years old and they all have the single SD1446 final in them. In over 20 years I have never blown a final - I have replaced the BF199 receive transistor from Lightning Strikes too close and the relays have failed but that is just minor cheap to fix problem. As far as output they transmit clean everyone says they sound great and many now own them and have never had a problem. Low Dead-key and not over 12 watt swing and they run cool and will last. I prefer the single pill SD1446 Final which I see in the latest update they changed to a MS1051,which I am not familiar with. Anyone who likes the Mosfets - NEWEGG runs deals all the time for 2 of the KL203P Amps for $128.00 and FREE Shipping.
The KL-200 is a Class "C" amplifier. You are most fortunate it has not popped the final.
The newer KL-203 is the Class "A/B" biased fet amplifier. These are good little amps for the money. The reason the are so touchy with power input is because the bias is around three volts DC. There is very little attenuation in the input/drive circuits.
I have some ham operators in my area and they all tell me that my old Uniden Grant sounds very good on sideband using the RM 203. I have been told they can't tell that I am even running an amp, other then a stronger signal. I have had this little amp for probably 5 years now and have abused it. It still works great. I have used it both mobile and with a power supply at my townhouse.
I have even had power supplies fail and over-volt them - the output power goes wild,but still has not damaged them. The 200's are really simple very few parts with a simple circuit makes repair fairly easy. You have one bf199 transistor on the pre-amp that will fail and the relays have issues which if you are careful you can remove the plastic cover and fix them. That has been my only problem with them.
It would be hard to build one yourself for what they sell for - NEWEGG sells them all the time for less than $65.00 with FREE Shipping and they are nice fused units I really like the quality for the price not just a copper-clad board with parts soldered everywhere very well made.
I like the 200 amps there is less parts to fail and simpler to find the problem - I gave one of the 203 amps to a friend that I got off E-bay for $25.00 and Free Shipping and there was nothing wrong with it and it works great with no problem at all it did not have the pre-amp which is mainly what I use my amps for and mine has less static with the Pre-amp turned on kind of hard to figure that one out.
That's the truth! The A/B set up on the 203 is pretty good. It just needs to be modified to accept more input watts.
I stand corrected. RMItaly does still make the KL-200.
http://www.rmitaly.com/index.php/en/products/amplifier/item/735-kl-200-p
http://www.rmitaly.com/index.php/en/products/amplifier/item/735-kl-200-p
Do they not test the units before they ship them to see if the parts they put in them are up to specification. I got one of the newer models with the MS1051 and it kills the receive when either transmit or receive is switched on. I tried searching for the MS1051 Transistor is what got me on this thread - no-one carries that transistor and there is no information on a replacement,I was checking to find any information to fix the new version 5.01 got the service manual but have not had time to check it out further. My mother has Alzheimers and it is a full-time job taking care of her - you only get one mother so she comes first.
Thank you and all the others on here for keeping the hobby alive - if it is not enjoyed and shared it will die.
I have no sources for the 1051 and I'm sure it is a relabeled industry standard part.
I can't say anything about their testing program because I don't know. I can tell you in the A/B biased MS1051 has to have 75ma quiescent current with nos signal applied.
I do have some MS-1051's that have not been installed and can get the
specifications of it as far as gain etc. I'll supply the data and somebody else can find a replacement for it. There are some that are labeled D100 that seem about right and I'm sure those are relabeled commercial products.
Hey Tallman: Ever seen any mods...
Or can be it done to take like 10m in a HLA-300 ver.1( I think) w/1446's and convert one band to be used on 6m/SSB??? Just a thought. Was trying to figure a way around mounting 2 different amps for mobile.
All the Best
Gary
I will look for reply when I get back from Chicago possibly Monday!
Or can be it done to take like 10m in a HLA-300 ver.1( I think) w/1446's and convert one band to be used on 6m/SSB??? Just a thought. Was trying to figure a way around mounting 2 different amps for mobile.
All the Best
Gary
I will look for reply when I get back from Chicago possibly Monday!
I do not know the answer to that and it would take engineering beyond my capabilities at this time. It has been a long time since I got that nerdy. Two strokes ago I could have.
Ten meters and six meters are pretty far apart in frequencies and I do not know if the circuity would be up to that. Circuit board layout could be touchy in the higher frequencies. RF design can get crazy at times. One piece of military gear I worked on you did the tune up of the transmitter circuits out side of the cabinet by bending these little aluminum tabs for a peak at a certain frequency and all of these adjustment interacted with each other. When you slipped the transmitter section back in to the case it would either go up too high or too low in power.
Not knowing this I caused one to melt down. I lost a stripe too.
It is also where I learned about "Harmonic Suppression"
Ten meters and six meters are pretty far apart in frequencies and I do not know if the circuity would be up to that. Circuit board layout could be touchy in the higher frequencies. RF design can get crazy at times. One piece of military gear I worked on you did the tune up of the transmitter circuits out side of the cabinet by bending these little aluminum tabs for a peak at a certain frequency and all of these adjustment interacted with each other. When you slipped the transmitter section back in to the case it would either go up too high or too low in power.
Not knowing this I caused one to melt down. I lost a stripe too.
It is also where I learned about "Harmonic Suppression"
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