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What amp?

Thanks for all the information on the amps. I really do appreciate it. I’m just getting back into the radio world after 40 years. Amps are new to me so I’m doing my best to understand what I need to do before making bad decisions. I’ve already bought a pair of kl 203’s overdriven them ... repaired one bought a kl 300 and that one is doing good so far.

my plan is putting the 300 in my truck with the galaxy dx 979 f and getting the bigger amp for the base station, galaxy dx 2547 with a hy-gain sp 500 about 75’ off the ground.
The new kl 300 was actually a used unit so I contacted the seller and they are working a deal on a kl 703 for my inconvenience..... we’ll see what they kick back lol.

The CarlBuilt sounds like a nice unit !
 
I'm really impressed with it. Since it's a high drive, you do need 20-30w to get to ~500pep, but most of my radios will do that. The way the fans work is very nice, (spin up on key down). It is huge!
The 703 is a well built amp and the power transistors are cheap if you do blow it up.
Its the biggest of the lot.
If it will fit in your car and suits your budget, then that's the one to get.
 
Okay here are pictures of the Texas Star DX500, RM Italy KL-503hd, RM Italy KL-703 and the CarlBuilt 400hd. Disregard the connectors that what’s I put on. Also disregard the word SLINGSHOT on the top of the CarlBuilt 400hd.

The Texas Star DX500 and KL-703 put out roughly the same wattage 450 give or take. That is not over driving them and using a Cobra 29 LTD Classic with about 4.5 watts dead key and 24 watts PEP. The KL-503hd does right at 300 watts as advertised. The CarlBuilt will exceed 600 watts output and is capable of being driven harder.

I don’t drive any of my amplifiers hard that goes for my Acom 2000P and Ameritron AL-82 both on 240 voltage and both exceeding 1500 KW.

I think the Pre-amp if that is something that interest you is superior on the RM Italy amps. If you’re looking for better tuned inputs (radio to amp) the RM Italy or the CarlBuilt are superior to Texas Star.

If you want to drive the amp hard both the RM Italy take up to a 30 watt input and they are more forgiving of a higher than 1.5 SWR on your antenna.

The CarlBuilt can easily take a 100 watt input. I don’t think it is as forgiving with high SWR

Inside the amps the Texas Star and RM Italy use a more finished circuit board. A few connections in the CarlBuilt are point to point soldering....meaning wires twisted together and then soldered.

Which do I like the best....my Acom 2000P, AL-1500 and AL-82 which are connected to my 10K Colossal 5/8 ground plane. The other antenna is a Sirio GainMaster 5/8 wave vertical dipole which I don’t push pass 450 watts.

Which amp will last longer between Texas Star and RM Italy I give the nod to RM Italy lasting longer. I think the CarlBuilt would outlast them both. The RM Italy does have reverse polarity protection and I think is ascetically more pleasing. Note how large the RM Italy 703 is compared to the others.

In my opinion amplifier failures are generally user error....SWR issues, driving to hard, over volting, under volting, improper connections be they electrical or coaxial.

If the amp doesn’t come with a fan for cooling...plan on adding one. The CarlBuilt comes with a fan.
Do you know how many amp power supply is needed for the CarlBuilt?
 
Do you know how many amp power supply is needed for the CarlBuilt

No less than a 50 amp supply dedicated only to the CarlBuilt. I have two Astron VS 70 power supplies. At the very least I would purchase two Megawatt power supplies model S-700-12 run in parallel giving you 100 amps total capacity. The harder you drive the amplifier the higher the current/amperage draw. Also no less than 8 gauge wire.
 
Do you know how many amp power supply is needed for the CarlBuilt?

As a general rule you can figure a 10 amp draw for every 100 watts of power. So if an amp builder is claiming 500 watts output then plan on at least 50 amps. I would also factor in 20-30% extra form some head room. So in the above example I would go with at least a 70 amp power supply. Also by lowering the input drive some and not running the amp wide open you can lower the amperage draw. Your mileage may vary depending on what mode you talk on. (AM,FM,SSB)
 
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I just put an order in with Nate "Hopper" for a 4 x 2879 HG base amp biased for class B I left out preamp as either of my small mobile amps can run on the 50 amp ps I have as a driver and either of those have a preamp.
I will say however the base factor and biasing bumps the price. I think it was 820.00 vs a 4 pill mobile. But the base box uses 3 switchers and I beleive they are 40 amps ea. This will drop with voltage and draw so 90-120amp must be required for the 4x2879. I have also heard (only heard no hard proof) to stay away from DEI and that TX Star is building with those and FAKE toshibas which are relabeled DEI I beleive. Nate said he's 3-4 weeks behind due to waiting for PS from overseas so I wont have a operational report for a while.
I will say this. I texted Donkey stomper. Never a response. I texted Carl built. Never an answer. I texted "hopper" after seeing 2 of hoppers earlier boxes being repaired by Bbi and describing what was good and what had been changed by Nate as he grew as a builder and the PS crap affecting everyone (builders).
I felt comfortable with Nates build quality based on this and a couple of nates own videos. Anyway....HOPPER answered both of my texts within 10 min. The other guys never did. And to me, that counts for something.
I am not going to battle to give you nearly a grand of my money. I wont keep trying I'll walk to the next option. Had I found nate 1st I could have saved a lot of time and effort.
Will let y'all know how it goes once he gets the supplies and built and shipped.
 
I just put an order in with Nate "Hopper" for a 4 x 2879 HG base amp biased for class B I left out preamp as either of my small mobile amps can run on the 50 amp ps I have as a driver and either of those have a preamp.
I will say however the base factor and biasing bumps the price. I think it was 820.00 vs a 4 pill mobile. But the base box uses 3 switchers and I beleive they are 40 amps ea. This will drop with voltage and draw so 90-120amp must be required for the 4x2879. I have also heard (only heard no hard proof) to stay away from DEI and that TX Star is building with those and FAKE toshibas which are relabeled DEI I beleive. Nate said he's 3-4 weeks behind due to waiting for PS from overseas so I wont have a operational report for a while.
I will say this. I texted Donkey stomper. Never a response. I texted Carl built. Never an answer. I texted "hopper" after seeing 2 of hoppers earlier boxes being repaired by Bbi and describing what was good and what had been changed by Nate as he grew as a builder and the PS crap affecting everyone (builders).
I felt comfortable with Nates build quality based on this and a couple of nates own videos. Anyway....HOPPER answered both of my texts within 10 min. The other guys never did. And to me, that counts for something.
I am not going to battle to give you nearly a grand of my money. I wont keep trying I'll walk to the next option. Had I found nate 1st I could have saved a lot of time and effort.
Will let y'all know how it goes once he gets the supplies and built and shipped.
Nate is a great guy. He will always respond to inquiries in a timely manner and is always happy to help if you have any questions or concerns. You will not be disappointed in your new box. I have ten (yikes) hopper boxes and love every one of them.
 

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