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Uniden 980 amplifier suggestions


I've got a dx500v now, this radio only
pushes it to 300 watts. I also have a ts mod v
Before the 500( not to worry, radio only pushes
the mod v to 1w swing 14w, the 500 still keys 100w swins to 325w Amp does more with my cobra 25. Im looking for an amp
maybe with a driver. Suggestions?
 
I think the Texas Star 667V has a pre driver but some guys don't like the V(variable) part. Obviously it's weak link. Here's a forum thread talking about disabling the 667's pre driver. I posted it just to show that it has one.
http://www.worldwidedx.com/amplifiers/29834-bypassing-driver-stage-texas-star-667v.html
A tune up would help along with an Astatic Road Devil mic. All my radios have a greater PEP with the RD
Uniden BC-980 SSB Tune-up Report - YouTube


Bells mentioned something about how a 5 watt dead key would yield around 20 watts PEP.
 
Bells mentioned something about how a 5 watt dead key would yield around 20 watts PEP.



I was just going to suggest that. I've seen a few videos of his tunes on the 980 reaching almost 20W peak on the bench. I would expect the number to drop a little once installed in a real world, working environment. A tech bench is going to be as close to a "perfect" scenario as you can get. In an actual install, there are losses introduced. But the radio will still end up with about double the output to what you are seeing now. It might not be enough jump in wattage to make a big difference running the radio barefoot, but it could make a real difference for amp drive.

What I don't understand is why your Mod V is only producing 14W peak? It uses a 2290 transistor, which is capable of 60W @12.5V with a 10W drive. You have 8W going in which should give you almost 50W out @12.5V. You'll see more if you are running it at 13.8V. So you should be able use the variable power to adjust the output of the Mod V to a drive level that is proper for the TS500.

What are you are using for power supply? If you don't have enough amperage to feed the amplifiers, then they won't reach full potential.
 
I was just going to suggest that. I've seen a few videos of his tunes on the 980 reaching almost 20W peak on the bench. I would expect the number to drop a little once installed in a real world, working environment. A tech bench is going to be as close to a "perfect" scenario as you can get. In an actual install, there are losses introduced. But the radio will still end up with about double the output to what you are seeing now. It might not be enough jump in wattage to make a big difference running the radio barefoot, but it could make a real difference for amp drive.

What I don't understand is why your Mod V is only producing 14W peak? It uses a 2290 transistor, which is capable of 60W @12.5V with a 10W drive. You have 8W going in which should give you almost 50W out @12.5V. You'll see more if you are running it at 13.8V. So you should be able use the variable power to adjust the output of the Mod V to a drive level that is proper for the TS500.

What are you are using for power supply? If you don't have enough amperage to feed the amplifiers, then they won't reach full potential.

I was trying to help DXing440 . Sounds like his 980 hasn't been peaked. The Texas Star export models have specs on them.
The way the FCC has cracked down on retailers I'm not sure if you can buy an export amp nowadays.
Texas Star Export Feature Chart

Texas Star CW Transmitters






P.S. As I said before,an Astatic Road Devil mic can really drive up a radio's PEP if you cranked it up. The RD is perfect on my CRE-8900 but on my Galaxy DX-959 I run the mic 1/4-1/2 volume level for a good clean sound. I'll crank it up to 3/4's when I need to talk long,long distance and 4/4's is just too much modulation because it sounds forceful.
I'm seeing about 35 watts just talking and 43 watts with it cranked up,whistling.
 
radio only swings about 8 watts, any ideas for a good amplifier? maybe around 500 to 800 watts

First step is have a shop do a nice tune and alignment to the radio. After that what amplifier depends on how much you want to spend and if you alternator can keep up. A Texas Star 667 would match up well if set up right. AM dead key on the radio at 1.75 watts and then 12-18 watts peak would be perfect for a 667.
 
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First step is have a shop do a nice tune and alignment to the radio. After that what amplifier depends on how much you want to spend and if you alternator can keep up. A Texas Star 667 would match up well if set up right. AM dead key on the radio at 1.75 watts and then 12-18 watts peak would be perfect for a 667.

you hit the nail on the head. and add to that if ya do get a tuneup dont use that
mod v. they really like a low input. also do you got the variable all way to the right
and green light pushed out [so its off] THIS will allow full out put of texas star amps
if ya do already id say something wrong with the amp then
 
I was talking to both of you. The first two sentences were to you, the rest was to DXing440. I was just saying to you that I agreed with your suggestion of Bells CB. I was going to suggest to Bells CB as I've seen 20W 980s come from his bench.

Ok. I know that DTB worked wonders for my Uniden 505 I bought from him and had him tune it. It's capable of a six watt dead key and 30 watt PEP with a good power mic. Shoot,even the back of the radio gets fairly warm on extended conversations. I heard my 505 on talkback with my 2018 and it sounds good.
 
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they really like a low input. also do you got the variable all way to the right
and green light pushed out [so its off]


You are 100% correct they like a very low dead key, with the built in MOSFET driver you only need to tickle the driver.

The 667V has the variable on all the time regardless of the switch settings.



99% of the time i will not recommend the 667V because the driver is (imho ) too much drive with a hot radio in front of it making them prone to oscillation problems.
Even a bit of copper to help shield the driver section from the rest of the Amp would help.
As Shockwav and Mad Scientist and others have said many times the bias scheme is not the best by no means, BUT when you consider the other options offered by these type of builders it is better than most of the Class C no bias amps.
The TNT line that has a B bias and the Texas Stars are about the best choice now that Messenger is gone.

There was another builder, BOO that also built a very nice biased amp but I think years of fighting with users that wanted " More Watts" rather than Clean RF has dissuaded him from building as far as I know.....he has not been here for a while.


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.

RE:
Texas Star CW Transmitters


73
Jeff
 
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I wasnt going to interject here with this one because Ive been on this race track before. Ive operated radio for a very longtime and yeah I know so have alot of people but what Im going to say is imple and not what most think about but here it goes and you can research what I share with you for yourself just so you dont think I have no clue what Im talking about I always thought big big big power is better better better this is only true to a certain extent. This info is what we on the amater bands speak of as best comoon sense bang for the buck. You have to remember the rule of thumb that after a certain point the person on the receiving end will not see or even hear the difference Ive talked all over the world on different bands with a simple 100 watts out of a mobile and that is the honest truth There is lots of different sources for this information ;)


Power, dB’s, S-Units

I am doing this page because a lot of friends seem to confused about the relationship between the amount of power their radio transmits and the s-unit reading on the other end. Unlike Tool Time’s Tim Taylor, “More Power”, isn’t always necessary. If we remember the rules we are only supposed to use the minimum amount of power to make a contact; we are not supposed to be alligators, all mouth and no ears. How many times have you heard a station calling CQ and they are a good strong signal, stations are trying to answer the CQ and no one is coming back to them. One of two things could be going on, one way propagation or the transmitting station is transmitting beyond the range that they can hear, unless the station on the other end is pumping a lot of power as well. It is far better to have good antennas to pick up the signals, a good receiver to be able to pull out and amplify the tiny signals picked up off the antenna and a good set of ears listening to the receiver. If you have all this stuff then buy your amplifier to enhance your station; you will then have a better chance of picking up the distance no-amplifier stations wanting to make contact with you. .vrz6{position:absolute;clip:rect(441px,auto,auto,483px);}
нужно ли выписывать ся чтобы временно прописаться льготный проезд в общественном транспорте для военнослужащих увольнение по состоянию здоровью на почте зарплата маленькая рациональное использование водных ресурсов приходные документы на товар у чп национальный банк и его функции социальная доплата до 3 лет как производится оценочная стоимость дома бти конституция рф последняя редакция признать сделку недействительной наследники второй очереди день города проезд специалист в уголовном процессе его права и обязанности встречка лишение прав скачать образец договора купли продажи

So what is all this power, dB and S-unit talk we commonly hear. What does it mean in real terms and what does 1.5kW of transmitting power mean compared to say 100 watts?
dB is a ratio of power, it is expressed by the following formula:
latex.php
Here is a table of ratios using this formula, you can see that a power ration of 1.25:1 is 1 dB. The S-Meter on most, not all, but most radios is 1 S-Unit for each 6dB. Looking at the chart below we can see that a power ratio of 4:1 is 6dB. So in real terms that means that if a station is transmitting at 25 Watts to raise the S-Meter on the other end by one unit and increase in power by a factor of 4 will do the trick. So you dial up the power to (25*4) 100 Watts and the S-Meter on the other end, will go up one S-Unit or 6bB
Power Ratio

dB

Power Ratio

dB

1.25:1112.6:1 111.58:1215.8:1 122:1320:1 132.5:1425.1:1 143.15:1531.6:1 154:16100:1 205:171,000:1 306.3:1810,000:1 407.9:19100,000:1 5010:1101,000,000:1 60So your friend calls you on the radio and you give him a signal report of 30 dB over 9. You ask him what power he is running and the friend boast 1.5kWatts. Well your friend is throwing away a lot of money for nothing really. 30dB is a power ratio of 1,000:1. So you can tell your friend that 1.5Watts will give you an S-9 reading!
latex.php
Let’s look at another example, QRP. How many times do I hear people get really excited about a 5 Watt contact, lots of times! It is exciting and a lot of fun but what is the difference between a 5 Watt and 100 Watt signal? If the station receiving the 5 Watt signal is getting it at S-5 what would the station get the QRP signal at if they went to 100 Watts?
Well first look at the power ratio:
latex.php
therefore
latex.php

The stations S-Unit reading will only increase to an S-7. The normal human ear can only detect a change in sound volume after 12dBs increase or decrease. So you would only just notice the difference in in the 100 Watts compared to 5 Watts!
For those interested tune your radio to any of the NCDXF/IARU Beacon Project and listen for the beacons from around the world. They transmit on a time schedule so you can monitor them without really knowing CW. There are Beacon tracking programs out there that show you which beacon is currently transmitting. All you have to do then is listen and watch the computer. It is better to learn CW though, go on give it a go! The beacons transmit at 22 WPM 100 Watts followed by four tones each tone is a the following power level: 100W, 10W, 1W, 100mW. You will be amazed at the number of times you can actually hear the 100 milli Watt signal for a far away land.
 
I agree, the 667 can be cranky. My first pick is usually a TS500v over a 667. In this example since he has a low powered radio and wants 500-800 watts it seems to fit the bill at maybe 550 watts.
 
Uniden 980 (not peaked, not enough of a gain to fool with$wise) modulation pot is turned up to max pep. Usiing an extreme 2018 mic. And a TS500V. Radio is set @1/2 watt carrier ( which yields a 100W carrier from the amp, then swings to 300W PEP)
If the mod v is installed between 980 and TS500V, 980 still 1/2W carrier, adjust the mod v to 3W carrier, yields a 125W carrier from the TS500V . Mod v still only swings to 14W from a 3w carrier, which still only pushes amp to 350W . Antenna iss wilson5000 thru the roof with 1.2-1.3SWR across the 40 channels
 

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