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Hdn9587
New member
Username: Hdn9587

Post Number: 1
Registered: 9-2006
Posted on Friday, September 29, 2006 - 6:13 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Had a 29 ltd that would dead key 2 and swing 20 to drive the 250.Just got a copper Cobra 150 gtl dx today.Wondering how well would the 15 watt deadkey swinging 45 work out with the 250 amp Thanks for any input hoping to install it tonight if I get a semi decent response
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Hootyal
Intermediate Member
Username: Hootyal

Post Number: 172
Registered: 9-2002
Posted on Friday, September 29, 2006 - 7:38 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

smell somthan burnin??? 15 deadkey gonna kill it....turn deadkey backdown to orignal 2 watt and maybe ok
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Hdn9587
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Username: Hdn9587

Post Number: 2
Registered: 9-2006
Posted on Friday, September 29, 2006 - 8:30 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Could anybody provide the procedure to get DK back down to 2 watts I saw the copper mod forn vr 12 is that where I start?
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Hotwire
Senior Member
Username: Hotwire

Post Number: 1830
Registered: 1-2005


Posted on Saturday, September 30, 2006 - 3:55 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hdn9587, Are you talking about a 250 watt amplifier? What transistors does it have? 15 watts dead key is way to much for any 2 pill amp. You want to have a deadkey of 2 watts. A 45 watt swing is going to greatly reduce the life of the 250 watt amp also. Lets say your amp is a Texas Star 250. The way you used the amp before with the Cobra 29, 2 watts DK and 20 swing was perfect and you do not want to drive it any harder than that. Unless you prefer to sound like poo and destroy the transistors. With a Cobra 150 GTL that is capable of 50 watts output I recommend to do it right with a 4 pill 500 watt amp like the Texas Star DX500v. Amps just do not need very much input at all to get 100 percent performance from them.
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Hdn9587
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Username: Hdn9587

Post Number: 3
Registered: 9-2006
Posted on Saturday, September 30, 2006 - 8:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sorry about not clarifing The amp is a Boomer 250 unsure of the transistors. Loved the little amp with the 29. Couldnt beat the price of the 150 though.Just wondering if there is a procedure for lowering just my DK and still keeping the swing. I was even able to sweettalk the better half for this one(150) Probably hard to sweettalk a bigger amp Thanks Chris
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Dx431
Senior Member
Username: Dx431

Post Number: 1187
Registered: 2-2002
Posted on Sunday, October 01, 2006 - 9:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ok, stupid question time. Why is it when someone buys a dual final export that dks 8w and swings infinity, then detunes it to drive an amp?
Isn't that whole idea behind the export rigs? Because it has more power than a CB? The average CB will drive most amps just fine. Buying an export rig just to detune it is a waste money.

JMO
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Hotwire
Senior Member
Username: Hotwire

Post Number: 1847
Registered: 1-2005


Posted on Monday, October 02, 2006 - 2:38 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

There is many different reasons why one would buy an export rig. Myself I use an export rig because the qaulity is much better than most regular cb's. I use SSB most of the time and the exports have dual clarifiers, freq counters and the SSB performance is so much better than most standard cb's. Also I like to venture into the freeband most of the time and the exports are ready from the factory. Of course the exports have more power but I can really care less about it. The difference between the power from a single final radio and a dual final radio is not that much and is hard to notice on the recieving end. I prefer to use an external amplifier.
To operate an amp your not really "de-tuning" the radio, your tuning it better. Your adjusting the deadkey to swing ratio to get the best performance from the amp. An 8 watt deadkey is just to much for most low drive amps and will desroy them.2 watts is the recommended deadkey most used. The bigger dual final radios are perfect for a 4 pill amp.
The single final radios are perfect for a 2 pill amp.
Can you run a single final radio into a 4 pill amp? You sure can and it will work great but the use of a dual final radio will get the max out of those 4 pills.
Can you use a dual final radio to drive a 2 pill amp? You really should'nt. Most setups like that are not good for long QSO's, overheat, sound like poo and will eventually die. Use of a custom amp instead of a commercial amp then you might be OK. Customs are made to handle higher temperatures.
So I use my beloved export rig with its wonderful features, qaulity construction, perfect audio and full wattage output but 2 watt deadkey to drive my 4 pill amp just right. Adjusting radio wattage allows the amps output to be right where it should be for the correct deadkey to swing ratio and long amp life.
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Hdn9587
New member
Username: Hdn9587

Post Number: 4
Registered: 9-2006
Posted on Monday, October 02, 2006 - 3:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Dx431 I could'nt pass it up at $60 bucks I haven't given up on old reliable just hoping there was a chance for the new rig to take the place of old reliable Thanks
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Hdn9587
New member
Username: Hdn9587

Post Number: 5
Registered: 9-2006
Posted on Monday, October 02, 2006 - 3:23 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Looks like I should keep my eyes peeled for a 4 transistor amp Maybe mama will get me a TS 500DX ...... BTW the $129 modulator kit(that is an option) is not needed due to the final drive of the 150 Correct?Thanks for all the input(Hotwire) and all the kind words(Dx431)
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Hotwire
Senior Member
Username: Hotwire

Post Number: 1849
Registered: 1-2005


Posted on Tuesday, October 03, 2006 - 2:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hdn9587, The modulator Texas Star V-Mod, if thats what your refering to is needed to drive the 8 pill amps. I have heard of people using it on the DX500 but I can't imagine why you would want to do that. In fact I would never drive my DX500 that hard. Plus your 150GTL is to much radio for the V-Mod.
Your 150GTL will match up to the Texas Star DX500 perfectly! Make sure the radio has around a 2 watt deadkey and let it swing! You will be very happy with that combo.
In fact I own 3 DX500 amps.Base/mobile/backup In the mobile I run a Connex 4800. 2 watt deadkey and 38 watts swing with a Predator 10K. One smokin mobile setup!
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Hdn9587
New member
Username: Hdn9587

Post Number: 6
Registered: 9-2006
Posted on Tuesday, October 03, 2006 - 2:42 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hotwire, how can I get this rig to DK 2 watts and swing away.Is there a modification available to DK 2 watts .Looking for instructions to set up/perform said mod.This was where i was eluding to from the start I was thinking along the same lines that the radio would take the place of the mod kit. I'm just trying to come up with a way to Dead key 2 Watts and keep my $60.00 swing
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Hotwire
Senior Member
Username: Hotwire

Post Number: 1853
Registered: 1-2005


Posted on Wednesday, October 04, 2006 - 2:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hdn9587, You need a reliable watt meter, one that is accurate and you trust and a dummyload. It has a low and a high power switch if I am correct. Check both setting and see what you get. Chances are that in the low power setting you might have what your looking for. If not, look to the right of the screen and click modification list. Find the 150 GTL-DX. Since I have never had the opportunity to use one of these radios yet or make any adjustments myself I can't really say exactly how to go about making adjustments. If you do try it be sure to make only itty bitty little adjustments at a time so you can put it back where it was if you don't like what your getting.
I don't recommend doing it yourself unless you have an idea what your doing.
I would take it to a qaulified technician keeping in mind that if you do have someone work on it other than the factory the warranty would be voided.
If all you have is a watt meter and an antenna then first just try to see what the radio is doing as it is. You may be in luck.
Lets hope some more 150 GTL DX owners get in here soon to help ya out a little better

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