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Recommondation $600 to $750

kevin IB/379 Stringbean said:
Citizens Band Related> General Discussion> , Didnt realize I was off topic..Sorry
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OFF TOPIC , BUT LIKE I SAID , I DON'T THINK I MISSED THE BOAT AFTER ALL. There's to many of you guys out here twisting this whole Forum change around in your heads to the point that your really beginning to think there's some kind of big change around here , THERE'S NOT !(just a new Forum format aimed at all) There's only big change up between many of your ear holes. A mountain out of a mole hill comes to mind. You said it yourself BM , Just go with the flow dude ! If IM try'in , IM die'in :( if IM do'in , IM improve'in. :) Peace
 
moleculo said:
What is supposed to be sold in the U.S. is actually a QRP 10 meter trasmitter that transmitts less than 5 watts RMS. They're not "amplifiers" per se.
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I'd like to see one of these "cw transmitters" connected to a power supply with an antenna and a key, and observe RF output from the "transmitter". Do they have a crystal socket, or a VFO? If so, where might it be? :confused::thumbdown:
 
I've seen 'em. They have a crystal socket where you put in the crystal for the frequency you want. They have a key jack also. I've actually seen this done and working.
 
I'd like to see one of these "cw transmitters
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I have seen a couple here, As Mole said, they have a board for a crystal to set the frequency in the Ten meter band.
The board is internal.
Here is a link to the Schematic:

http://www.texasstar.com/350HDVschematic.gif

X1 is the crystal plug.

From The T/S web site:

These transmitters are designed for mobile or base CW operation. Powered by the 12 volt vehicle battery or 12 volt regulated power supply, the maximum power output is less than 5 watts RMS. Frequency of operation is within the 10 meter band, determined by installation of a crystal into the oscillator board. The transmitters contain a transmit/receive relay and an output connector for the receiver to share the antenna and permit break-in operation.

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 as follows:
    • "DIAL-A-WATT" switches the power output potentiometer into the circuit on models that feature variable power.
    • "SELECT-A-WATT" switches the output to low power on models without a variable control.
  • Yellow "DELAY" Button reduces power and adds delay to the transmit/receive relay to accommodate different transmission rates for break-in keying operation. (A Delay Rocker Switch is located on the back of those models that have only three push buttons on the front.)
  • Meter is an RF Relative Output Indicator and lights during transmission.
  • A Crystal made for series operation must be installed into the holes labeled "X-1" near the top of the oscillator board. The frequency should fall between 28.0 MHz and 29.7 MHz.
  • Key Jack for 1/8" miniature phone plug is located on the rear of the unit for connection of the telegraph key.
  • Power Cables are also located at the rear. The yellow lead connects to the positive side of the power supply, and the black lead connects to the negative side.
  • Antenna Connector (SO239) for 50 ohm antenna is located on the rear.
  • Radio Connector (SO239) for 50 ohm output to the receiver is also located on the rear
SPECIFICATIONS:
Frequency Range
28.0 MHz to 29.7 MHz
Stability
50 parts per million, 0-50 degrees Celsius with typical quartz crystal
Power Output
< 5 watts
Voltage
13.6 volts DC
Amps
< 4
Impedance
50 ohms
Duty Cycle
100% at full output
Harmonics
> 30dB down
Dimensions
3-1/4"(H) x 5-1/4"(W) x 8"(D)
Weight
3-1/2 pounds
Click to expand...

I have it from a good source that with a little work, by a properly licensed Ham, they can be modified to work on the Ham bands as an Amplifer.

73
Jeff
 
talk about headroom
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Same Spec for the DX 1600 CW transmiter and other models

CW Transmitters (Models SK 220, MOD PLUS, MOD V-PLUS, DX 1200, DX 1600 and Accessories)

These transmitters are designed for mobile or base CW operation. Powered by the 12 volt vehicle battery or 12 volt regulated power supply, the maximum power output is less than 5 watts RMS. Frequency of operation is within the 10 meter band, determined by installation of a crystal into the oscillator board. The transmitters contain a transmit/receive relay and an output connector for the receiver to share the antenna and permit break-in operation.
SPECIFICATIONS:
Frequency Range
28.0 MHz to 29.7 MHz
Stability
50 parts per million, 0-50 degrees Celsius with typical quartz crystal
Power Output
< 5 watts
Voltage
13.6 volts DC
Amps
< 6
Impedance
50 ohms
Duty Cycle
100% at full output
Harmonics
> 30dB down
Click to expand...

73
Jeff
 
Switch Kit said:
OFF TOPIC , BUT LIKE I SAID , I DON'T THINK I MISSED THE BOAT AFTER ALL. There's to many of you guys out here twisting this whole Forum change around in your heads to the point that your really beginning to think there's some kind of big change around here , THERE'S NOT !(just a new Forum format aimed at all) There's only big change up between many of your ear holes. A mountain out of a mole hill comes to mind. You said it yourself BM , Just go with the flow dude ! If IM try'in , IM die'in :( if IM do'in , IM improve'in. :) Peace
Click to expand...

PEACE,Your right and Im wrong!!!!!Its all good
 
easy bean , it's all good in the forum neighborhood. Just do your thing as you would any other day. There are no big deals in this life unless we choose to have them. Your choice dude. always good to see you around. Peace
 
900 watts from 1 x 2SC2879 transistor driving 4 x 2SC2879 transistors . according to toshiba http://www.datasheetcatalog.com/datasheets_pdf/2/S/C/2/2SC2879.shtml a single 2879 needs 6 watts typical and 10 watts pep to achieve their full rated output of 100 watts pep . there apparently is some headroom where the 2879 can produce more power and still be reasonably clean , i would think 225 watts per final device is way beyond that point . also at that level i bet a good percentage of those 900 watts are not even on the channel youll be txing on .

1x2 and 1x4 and 2x4 amps are for folks too cheap to buy an amp with the necessary pills to achieve the power level they want . if you want 900 REAL watts at least get a 6 pill . depending on the radio you have you may not even need a seperate pill driver stage . what radio are you running and what kind of DK and swing are you getting ? heres a nice 6 pill http://ampsrus.net/product.sc?categoryId=10&productId=255 and you still have the option for fairly clean SSB use in the future.....if you choose to go there .
 
Data for the 2sc2879

P Out 120 watts, by Pin 7 watts, Gain 30 mHz 15 dB,
These data with power output staying within the 1 dB compression point, and delivering an clean signal after an decent filter.

So, explain to me how 6 of these will deliver 1600 watts output power taking the coupling losses and filter losses in mind??

Or are those the DC input power claims...

In an P.A. for an ham transciever 2 transistors each capable of delivering 100 watts are used for an 100 watt P.A. stage.

Going from there i would see 400 to 500 watts max for this setup, clean after filtering.

Printing something on the outside of an box is easy..
 
It won`t and stay anywere near a clean rf signal, If you look at the one web site (the one with the 6 x 2879 device) it says 400 watts avg and 750 PEP...... at 14.2 or so volts from the avg car/truck, that sounds about fair.

Printing it on the outside of the box is good for sales, the first time.

73
Jeff
 

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