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Hoskinmage
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Username: Hoskinmage

Post Number: 50
Registered: 3-2002
Posted on Wednesday, July 13, 2011 - 9:52 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i have just got a new ts667 and im going to run it with a vr9000(voyage) the radio is set up to key 1/4 wat and swing 30 and this is my first big moble box and i was kinda wondering how its suposed to act.how much key up do i need to use to drive it?i dont want to overdrive it on my palamar 400 i use 1/4 wat and it swings to about 275 to 290.im just not sure how to use the dial a watt and will i need to switch something to use side band?i been radioing for sometime but i have never run anything this big in my jeep(or anything els ive owned)i know i mite sound like a newbee but i just wanted to do this rite and sound good,because it cost to much to to fix it after i blow it up.any help and or informataion that could help.i sure would apreciate it.
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Sitm
Intermediate Member
Username: Sitm

Post Number: 460
Registered: 1-2004


Posted on Thursday, July 14, 2011 - 10:57 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Remember the variable wattage knob works on the TS 667 in all modes, not just dial a watt. I personally would not drive it with any more than 20 watts pep ever. This amplifier is designed to be driven with single final radios. This is why it has its own driver. You will achieve this amplifiers maximum pep output easily with a regular single final radio. I can almost assure you that if you drive it with a dual final radio you will have great numbers, for awhile. I would say that you would have been better suited with a TS 500. Remember you have 1-2SC2290 driving 4-2SC2879. Hence the reason this amplifier was created was for single final radios to achieve full output on a four pill amplifier. You will have people posting on here that they drive theirs with a dual final for years and have had no problems. I am telling you what they were designed for and intended to be used for. I would never purchase a TS 667 from someone who had been driving it with a dual final radio. The "pills" transistors are going to be thrashed eventually and the excessive wattage you are getting is going to be splatter and not clean broadcast. In the end you can do what you want, but you asked. Let the experienced techs chime in on this one, maybe I am off base.
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Dale
Senior Member
Username: Dale

Post Number: 1737
Registered: 12-2002
Posted on Thursday, July 14, 2011 - 5:42 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

the dk sounds ok. but the swing may be a tadf high. id use a noise canselling mike then if
still nessary back down the mic gain.remember
this particilar amp has a BUILT IN DRIVER so it needs very little drive.on ssb id turn down the ssb power inside radio to about 12-18 watts .
for the variable power dont use it. push out
the green button and just use the power on the radio itself.this amp is better suited for a low power radio like a galaxy 959,or even better
a cobra 148/grant style radios,but if ya turn down radio on the inside to match the power of a
148 /grant ,ect then should be able to use it
dale/a.k.a.hotrod
cef426
cvc#64
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Sitm
Intermediate Member
Username: Sitm

Post Number: 461
Registered: 1-2004


Posted on Friday, July 15, 2011 - 9:59 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The Texas Star DX 667 variable power works regardless of if the dial a watt is on or not.
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Moonraker
Intermediate Member
Username: Moonraker

Post Number: 280
Registered: 3-2005


Posted on Friday, July 15, 2011 - 8:40 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Does the dial a watt button do anything? I've never owned one but am curious.
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Hoskinmage
Member
Username: Hoskinmage

Post Number: 51
Registered: 3-2002
Posted on Saturday, July 16, 2011 - 6:52 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i want everyone to know that i apreciate each and everyones coments and this has helped me some but if someone could explane how this box works like the dial a watt button and how and why the delay button is used and generaly how this box works.the bigest box ive used is my palamar 400 and its pretty much selfexplanitory.but im not sure how to use the 667 or what all the buttons is for,like when i use it on sideband do i use the delay button or is it likemy palamar it just does it automaticaly?ive tryed to research about the use on the cb band but i cant seam to find it.i just want to use it rite and to be a good radio operator.i dont talk much mainly to my wife and maybe a little skip once in awhile.this is a major investment for me and i want to do it rite. sorry for being so stupid about it but i want to do things rite
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Charliebrown
Intermediate Member
Username: Charliebrown

Post Number: 218
Registered: 10-2002
Posted on Saturday, July 16, 2011 - 10:16 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

NO PERSON START'S OUT KNOWING EVERYTHING AS SOME WILL HAVE YOU TO THINK. TAKE YOUR TIME AND YOU WILL DO FINE. MOST HAM OPERATOR'S START OUT JUST AS YOU. IT JUST WILL TAKE A LITTLE TIME AND WORK AND EXPERIENCE. THE TECH'S HERE WILL NOT TELL YOU WRONG. THE ONLY STUPID QUESTION IS THE ONE THAT IS NEVER ASK. YOU ARE WILLING TO ASK SO, YOU ARE NOT BEING STUPID. THING'S ARE CHANGING SO FAST NOW THAT NO PERSON CAN EVER SAY THEY HAVE NOTHING TO LEARN. HAVE A GREAT DAY AND ENJOY AND MAY GOD BLESS.
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Dale
Senior Member
Username: Dale

Post Number: 1739
Registered: 12-2002
Posted on Sunday, July 17, 2011 - 11:53 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

red button= main power on/off
white button = pre amp [not really used]
green button =deactivates the variable and amp is set to wide open. my 250 /and 350 is like that may wanna try yours first
yellow button=is ssb delay when using ssb make sure its pushed in
dale/a.k.a.hotrod
cef426
cvc#64
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Sitm
Intermediate Member
Username: Sitm

Post Number: 462
Registered: 1-2004


Posted on Monday, July 18, 2011 - 10:07 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The Texas Star 667DXs dial a watt works with the variable power on or off. States so on the Texas Star site and I own one. On this particular amplifer the variable power button when activated cuts down your wattage input to the amplifier only. Variable power works all the time regardless of if the button is on or off.
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Sitm
Intermediate Member
Username: Sitm

Post Number: 463
Registered: 1-2004


Posted on Monday, July 18, 2011 - 10:14 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Below is directly from the Texas Star web page. Please note that according to their site "ONLY" the 667 the RF knob is operational AT ALL TIMES.

http://www.texasstar.com/CWmed.html

OPERATION:

Red "POWER" Button turns the unit on and off.
White "REC AMP" Button turns the receive amplifier on to provide 6dB of gain for your receiver. This will work independently of the power button -- that is, the white button may be pressed "on" even when the red button is "off." The oscillator may be operated without any output to the antenna. You will be able to hear the signal in your receiver. This may be useful to adjust your electronic keyer or to practice your Morse Code "off the air."

Green Button reduces power on all models. On models DX 400V and DX 500V, it also activates the RF Output Knob.

Yellow "DELAY" Button reduces power and adds delay to the transmit/receive relay to accommodate different transmission rates for break-in keying operation. On models DX 400V and DX 500V, this button adds delay but does not reduce power.

RF Output Knob controls RF output level when the Green Button is engaged. On the DX 667V only, the RF Output knob is operational at all times.
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Sitm
Intermediate Member
Username: Sitm

Post Number: 465
Registered: 1-2004


Posted on Tuesday, July 19, 2011 - 12:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

This was posted by Tech 181 on December 11, 2001. I am re posting it because of the knowledge containted there in. See entire thread on this link at coppers.

http://www.copperelectronics.com/discus4/messages/34/8412.html?1009745017

Posted on Tuesday, December 11, 2001 - 9:25 pm:

--------------------------------------------------------------------------------
I have heard and seen a lot of claims regarding output power as it pertains to amplifiers. Some people make some of the most outlandish claims regarding the amount of power a transistor (also called "pills" because of their resemblance to aspirin) are capable of.

In my experience, I have found that no matter how hard you drive an amplifer, it DOES have a ceiling as to how much power you can get out of it. Allowing your input to maintain an output constantly near that ceiling will result in a shortened life of the internal components, especially the pills.

Some people claim you can get 900+ watts out of a Texas Star 667. This is just not true. I don't care what you do to that amplifier, you will not get that kind of power out of it. Heavier wire, extra batteries, bigger alternator, etc. will NOT give you ANY more power out of this particular piece of equipment that the transistors can produce. Of course bigger power wire, and a larger alternator will help you achieve the maximum output and effiency from the amp, you will not get more out of it than it can possibly produce. Period.

How much power can you get out of an amp? That depends, of course the amplifier you are running, and the way it is installed and set up. Be sure to use heavy gauge wire for long runs and be sure your alternator can handle the load. Putting a 667 in a Ford Festiva is asking for trouble. Be sure your alternator will be able to handle the load of your amplifier while still being able to use your headlights, heater, and other high amp accessories.

While proper installation using quality components is key, the rest is up to the amp itself.

Let's take a look at the Texas Star 667V. This rig is powered by one (1) 2SC2290 transistor driving four (4) 2SC2879 transistors. The main reason for the driver is to allow the user to get full power out of all four of the 2879 pills. Most radios lack the power to signifcantly power all those transistors to their fullest capability.

The 2SC2290 transistor is manufacturer rated at 70 watts. The 2SC2879 transistors are manufacturer rated at 100 watts a piece. Knowing this we can easily see this amplifer has one 70 watt transistor driving the four 100 watt transistors.

In my experience, I have seen that most transistors are rated kind of on the low side by the manufacturer that produces. This conservative estimate may be attributed to several things, but most transistors are rated on the low side nontheless.

From what I have seen and experienced, a transistor will put out 125% of it's manufacturer rated output. But this is it. Absolutely no more. Knowing this we can easily estimate the output of the 667 as 500 watts PEP. That's four 100 watt transistors performing at 125% which is an additional 25 watts a piece. Multiply 100 watts times four, and you get 400 watts. Add this total to the extra 25 watts out of each of those four transistors which is 100, and you get your grand total of 500 watts.

What does the "667" mean printed on the cabinet of the amp? Who knows? As with all the other amplifier manufacturers, the number on the outside is pretty meaningless. As far as I can see, it's a sales pitch. The bigger the number the "badder" the amp sounds, which in turn may generate more sales.

Some people throw meaningless acronyms into the equation like PEP and SSB. Well, PEP is Peak Envelope Power, the absolute top power possible, and since sideband emissions generally produce higher output power than AM emissions the false sense of a higher power through sideband use is produced. Hence people think they are getting a piece of equipment capable of putting out more.

The fact is, the amp is only going to put out as much power as it is built to put out. Driving the amp with more power (watts in) will only result in heat and potential damage to the amp. But it will NOT result in more power. You are only going to get out of it what it's built to do, not what someone says it will do.

"But I get more out of my amp than you say is possible! You say I can only get 500 watts out of my amp and I am getting over 550 out of it."

This is where I think alot of people get their inflated power outputs. It's called reflected power. You see, high SWR will be shown as higher output power, giving the false impression of more power out on the meter. The best way to measure your output is with a meter that shows reflected power by the way of a dual-needle meter or one that shows the relative percent of power reflected back at different levels of standing wave.

I am working on doing a review of the KL300P amplifier and my theory holds correct.

The KL300P contains two (2) SD1446 transistors, factory rated at 70 watts a piece. The most I could hope for was 87.5 watts each for a total absolute output of 175 watts. I was getting 180 out of it. However I had an SWR of 1.4:1. At this SWR I had a reflected power of approximately 3 percent. 3 percent of 180 is a little over 5 watts. Hence the actual forward power was around 174.6 watts. Pretty close in my book. I drove this amplifier as hard on both AM and SSB as I could and still could only get 175 watts out of it.

As you shop for an amplifer try and remember this. Don't judge the amp by what's printed on the cabinet or what the dealer says it will do. Find out how big the transistors are in the amp and how many of them there are. Then you will be able to make an educated assumption as to the REAL power output. Below I have listed some commonly used transistors and the power output rating put on them by their manufactures.

Happy DXing!

2SC2290 -- 70 Watts -- 87.5 MAX
2SC2879 -- 100 Watts -- 125 MAX
SD1446 -- 70 Watts -- 87.5 MAX
MRF455 -- 60 Watts -- 75 MAX
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Onelasttime
New member
Username: Onelasttime

Post Number: 2
Registered: 8-2011
Posted on Friday, August 05, 2011 - 5:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Back when I ran a 667 I replaced the 2290 with another 2SC2879 and had it set up to work like a modulator amp so I had tons of swing. I was using RCI2950 in fact the first owner of one in my area back in 1991/92. I worked at an electronic repair shop so I always set up gear like I was setting up amateur equipment with regard to spurious emissions clean modulation properly limited and proper filtering. So with that said and the RCI properly aligned and aka peaked and tweaked....LOL I found that my 667 ran cleanly on the scope with my RF power knob set to 12 O'Clock position which is also where I normally ran the radio when not driving my amp. So I would set up the radio in this manner.

As to single final or double that is kind of not a good rule of thub and hear is why. I was in H.S. at this time and my best friend had a Uniden Grant XL with Expo kit. His single final Uniden cleanly put out 36 Watts on AM with a single 1969 final while my dual final RCI could only muster 32 watts cleanly on AM with it's dual finals. So really his single final radio with no RF power output control would drive a amp far harder then my RCI dual final radio and full power. So at 12 O'Clock my big bad evil dual final radio was something like 10-12 watts swinging to 32 watts. If I turned it all the way down for QRP I was at 1 power I watt with almost no swing I think it was 1 watt swing to 4 watts....At full power it was 32 watts no swing.....Mind you I am going from Memory someone stole that radio about 9 years ago so my memory is fuzzy.

So I would say at the very least use a good modulation and power meter and set the radio and amp up right. Even better if you can put the combo on a scope shot it into a dummy load and adjust it so that it is absolutely perfect.

A properly set up radio and amplifier can not be over driven because you set it up so that at full output you have the fullest clean RMS output power . You should not even be able to over drive the amp because that serves no purpose it does not make you talk any further those added watts are spurious emissions and while they look good on a cheap meter they do nothing for you talking power. All it does is get into your neighbors TV, opens and closes garbage doors and bleeds over 5 channels each direction.

If I could not use a scope I would prob. set up an amp to put out at max RF output a wattage that was .5 x peak ouput because this would surely guarantee that you did not have a splater box. Linear amps almost never approach the .707 number for RMS power unless the voltage of your vehicle is 14.5 or higher and all the transistors are high beta and matched.

I am sure some will think it is stupid not to run the amp hot,loud and splattering but I think clean sound is all that counts.
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Onelasttime
New member
Username: Onelasttime

Post Number: 4
Registered: 8-2011
Posted on Saturday, August 06, 2011 - 12:08 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You know I could be remembering the TS 500HD I had.......I know my boss though used his RCI2950 to drive a 667 with no problems at all though. That is the beauty of the RF PWR knob!Either way with either an RF PWR knob or a high low switch you should be fine even with a dual final radio is my point!
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Dale
Senior Member
Username: Dale

Post Number: 1753
Registered: 12-2002
Posted on Saturday, August 06, 2011 - 7:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

onelasttime, i agree completely about the splatterbox.however on the 667 i disagree.
i used a uniden washington and 667 in the house
and the washington just having a slight tweak
in the audio and dead key cut back around 1 watt
i was getting over 400 wiskeys. with a 2950 that
would push it quite hard.i dont doubt what he had ,but he must have tuned that 2950 so it doesnt do much more than a single final radio
dale/a.k.a.hotrod
cef426
cvc#64
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Sitm
Intermediate Member
Username: Sitm

Post Number: 466
Registered: 1-2004


Posted on Tuesday, August 09, 2011 - 10:08 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

In the end, use it the way the manufacter suggest. You can reach full outpout with this amp using a single final radio. The manufacter recommendations on input would be exceeded with a dual final radio. So you decide, run it the way the company you purchased it from suggest, or run it the way someone you don't know suggest? Your' call. Personally I would not run a TS 667 with a dual final radio. That is what a TS 500 is for. Why, because that is what the manufacters specifications suggest and I reach full output with a single final radio. More isn't always better, unless its money.
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Sitm
Intermediate Member
Username: Sitm

Post Number: 467
Registered: 1-2004


Posted on Tuesday, August 09, 2011 - 10:15 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Single final radio, not some magic screwdriver hyped up, capacitor changed radio. Run the radio as specified by manufactuer recommendations. Generally if someone is "replacing" the driver in a 667 it is because it was blown.

Lets simplify this right down to the bare bones. Run the amplifier to specifications.
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Sitm
Intermediate Member
Username: Sitm

Post Number: 468
Registered: 1-2004


Posted on Tuesday, August 09, 2011 - 10:17 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

A high low power knob or variable power knob on the amplifier only changes the output of the amplifier. It doesn't change the fact that you are overdriving the "driver" in the amplifier.
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Hoskinmage
Member
Username: Hoskinmage

Post Number: 52
Registered: 3-2002
Posted on Wednesday, August 10, 2011 - 12:31 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i realy want to thank everone that has given me advice i will at some point use every peice of it and i promas that i will try to be the best cber i can be,no fussing,no cussing and i just love to sit around and talk joke cut up and have fun like we used to do years back.i dont like to argue or fuss and fite all i wan is to radio with a good bunch of people and have FUN life is to short to fite and scrach and cuss,remember the old days everone helped everyone,when someone had an antanna that needed to go up we simply had an antanna raising we helped eachother it didnt matter who walked on who we just had fun and i,for one enjoyed my radio and i got to meet some real good people along the way.wonce agin THANK YOU for all your help.and always remember to enjoy your radio and have fun doing it
73's and may god bless
snowman,in lincoln co. ky

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