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Texas Star 500V vs Davemade 4 Pill

weatherman

Active Member
Sep 23, 2011
45
42
28
OK, I have a Ranger 2970N2 that I got new and had it turned down to a 5 watt deadkey for the Texas Star that I have and have not put inline yet. Got to scratching my head and was wondering with all the swing the 2970 has, will the Texas Star last? Should I go with a Davemade 4 pill(not for sideband)? Will the 500 last on sideband? Should I shoot myself for turning down the 2970? Any help would be appreciated.
 

The 2970N2 is way too much output for the T/S 500, on both AM and SSB.

The Davemade 4 pill would work ok if you keep your input on it to about 100W swing on AM. On SSB, you'd kill the amp. Davemade amps aren't made for SSB, so as long as you're not running SSB with the Davemade, you should be fine.


~Cheers~
 
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Agree

I concur with the others. IF you can get the DK DOWN on the 2970 to no more than 2-3 watts you MIGHT be able to run the Texas Star. I personally would NOT recommend the DM. Just because it doesn't have SSB switching. I do have a Comp DM it was custom made with SSB. I bought it from a lady whose Husband had passed. I do not like it as it is not a very clean amp, being a comp. I may try to sell it...works good but too dirty for me. I do like a cleaner amp that won't bleed all over the place on people 40 miles away.
 
In reality you almost need an 8 pill amp IMO, I would just turn the radio back up to around 150-200 watts pep and let it ride. Get a good antenna system and you will talk a long ways. You didn't mention what antenna system you were running and to me that's the most important part of the system, besides having the radio. If you get a proper antenna setup, with 150-200 watts on ssb, you can talk around the world when conditions allow. But if you are looking into getting an amp for that radio you may have to step it up to an 8 pill or at least a good 6 pill IMO. But then you will need a larger charging system and will definitely need a proper antenna and power setup. That's JMO, but I would get the. 2970 turned up to around 150-200 watts pep and run it like that and see what you get. Make sure to use good power wires and ground everything good as well , and did I mention make sure to have a good antenna system. Good luck and god bless.
 
Either way, you will be overdriving the crap out of either amplifier. And while AM is more "forgiving" as far as how you might sound on the air, with either amplifier, you are going to be over driving it way past compression and saturation and creating a mess of junk out to the antenna. The dave made will handle it better because of its no bias design it might let you get away with it.

As far as turning down the 2970n2, to reduce the carrier that much and have it "swing" up that high is definetely creating distortion already. The positive peaks will be way too high, and the negative ones happen to be approaching "zero" for a finite amount of time during voice peaks. More splatter and distortion.

The proper solution would be to have the internal amplifier on the 2970 / 2970n2 put on a switch (which is easy to do, basically just inline with the wire going to the relay on the PA (power amplifier) board so it is running without the amplifier, then go with a DX500. Nice, clean output for the most part, everything will last forever and work right. If you ever get rid of the amplifier then you can turn the one in the radio back on.

If you *INSIST* on using the amplifier in the radio, then go with an 8 or 12 transistor amplifier. Even then, it's a bit much for the 8 transistor, but if the radio's AMC and ALC are intact and limiters haven't been removed or yanked out or played with, the ALC can be set to about 100 watts, the carrier to about 25 watts, and AMC for about 100 watts peak on AM, it will drive an 8 transistor amplifier nicely without splattering down the road and trying to squeeze every last watt out of everything.

My way of thinking is, if I want more power, get a bigger amplifier. I don't think I have ever burned up an amplifier, gone through tubes, or destroyed finals in my gear in the past 25+ years I have been playing radio.
 
They told me that same thing with my 2995dx that it would not sound right if i turned it down to 1.5 watts , well they are wrong ..I run a TS-500v Sounds great . Done it on a few of those radios ..


I hit the TS with 1.5 or 2 watts dead let it swing , hardly gets warm ..

I know we are talking about 2 diff radios here , but you might try turning it down some more before you spend more cash ...

Just my 2 cents worth means nothing !!!!! Have fun....
 
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Either way, you will be overdriving the crap out of either amplifier. And while AM is more "forgiving" as far as how you might sound on the air, with either amplifier, you are going to be over driving it way past compression and saturation and creating a mess of junk out to the antenna. The dave made will handle it better because of its no bias design it might let you get away with it.

As far as turning down the 2970n2, to reduce the carrier that much and have it "swing" up that high is definetely creating distortion already. The positive peaks will be way too high, and the negative ones happen to be approaching "zero" for a finite amount of time during voice peaks. More splatter and distortion.

The proper solution would be to have the internal amplifier on the 2970 / 2970n2 put on a switch (which is easy to do, basically just inline with the wire going to the relay on the PA (power amplifier) board so it is running without the amplifier, then go with a DX500. Nice, clean output for the most part, everything will last forever and work right. If you ever get rid of the amplifier then you can turn the one in the radio back on.

If you *INSIST* on using the amplifier in the radio, then go with an 8 or 12 transistor amplifier. Even then, it's a bit much for the 8 transistor, but if the radio's AMC and ALC are intact and limiters haven't been removed or yanked out or played with, the ALC can be set to about 100 watts, the carrier to about 25 watts, and AMC for about 100 watts peak on AM, it will drive an 8 transistor amplifier nicely without splattering down the road and trying to squeeze every last watt out of everything.

My way of thinking is, if I want more power, get a bigger amplifier. I don't think I have ever burned up an amplifier, gone through tubes, or destroyed finals in my gear in the past 25+ years I have been playing radio.

this is very good info. and i agree with it completely
 
Dropping down the n2's output to 60-100 watts and driving a high drive amp that loafs along @ 800-1k will obtain the goal one strives for when using an amplifier.
Going from 200 to 500 by dropping down the n2's output from 150/200 to 11/2 - 2 watts doesn't make sense.
The only difference will show on your external power meter and not on the other end where one wants it.
The 4 x rule always applies.
The objective to using an amp is to gain s-units/DB gain.
And if that won't be the outcome why bother? Good luck. 73's
 
a possible solution is have respectable tech install a toggle switch to turn amp off on the n2..or buy a 2950. last and most expensive option is buy a 8 pill amp . none of this is probaly what ya wanted to hear but to my best of knowledge this is where your at
 
I'm always amazed at how many people go and buy a hotrod radio, but then try and run it with too small of an amplifier. If your going to buy the big radio you have to also buy the big amplifier. Recently had a local with an old style 2970 (150 ish watts) and he told me he was going to add a Texas Star 350 Hiiii Driiiiive and really kick some butt.
 
If this is for a base find an amp with an 8877. Loaf the radio and amp to get 3 or 4 times the power of a 4 pill.
 
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Yes, you can install a "barefoot" switch that turns off the radio's internal linear.

We call that one the "Suicide Switch" when a customer asks to have it installed. Sure, we'll install it. But only after making it clear that Murphy's Law will always apply, sooner or later. It's not a question of "if", but a question of "when" the switch will be set to "high" when a low-drive amplifier is in line with the radio.

73
 
I put an on/off switch in a Saturn turbo for a friend. He wanted to be able to switch between a sweep tube amp and an 8 pill.

I put a safety in the tube amp so he couldn't screw up. The amp had to be connected to the radio with an rca cable and turning on the internal amp in the radio would put the tube amp in standby.
 

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