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Multiple accounts belonging to the same member will be deleted without warning. Cobra vs. Master Chief Guest. Joined: Apr 5, Messages: 1, Likes Received: Thestonerguy Active Member. Joined: Apr 3, Messages: Likes Received: 1. Joined: Sep 14, Messages: 1, Likes Received: Joined: Nov 20, Messages: Likes Received: Switch Kit Active Member.
Joined: Apr 6, Messages: 3, Likes Received: Joined: Apr 23, Messages: Likes Received: The original was from when the President CB company was still independent. There are various argument over which version is the best. I personally like having the final version, others say the originals were best.
No one seems to have much love for the transitional version. The basic differences between the three were:. This model also had the four pin microphone jack. The second generation also carried the President Label, used the same inside components but added a channel 9 button and an LED for the channel 9 indicator under the channel display. It also added a PA feature on the squelch knob. The Uniden had a 5 pin microphone jack speaker will not work if microphone is not plugged in.
Ham operators used it in just this manner, back before it was taken from them in the fifties and turned over to the CB service. HF frequencies are capable of bouncing around a bit and can end up anywhere in the world.
This does not always work, as the many CB operators who work skip will tell you. This presents some problems when setting up an antenna. A typical HF antenna is horizontally polarized - that is to say it lays on its side.
This is ideal for long range, SW type of communications. As a SW band, the 16' long wire that could be used for these frequencies is not much of a problem, you can put it anywhere. As a local band, the 9' to 17' high antenna can be a problem. I am a limited space read stealth operator, and am unable to erect any really big antennas. Initially, this set was operated on a horizontal dipole - probably the worst kind of antenna to use for CB, unless you are chasing skip.
A horizontal dipole has nulls at both ends, so your antenna will be deaf out the ends. It will also push a big portion of your signal into the ground, and another big portion right up into the sky. This doesn't leave much. To make matters worse, since the antenna is horizontally polarized, and most CB antennas are vertically polarized, there is something like 20 db of loss due to polarity differences. The only advantage to a horizontal dipole is that it is easy to build and mount.
It is essentially a pair of quarter wave long pieces of wire, strung out in opposite directions. I eventually ended up turning this antenna into a vertical dipole. You don't hear much about vertical dipoles, and for a while I thought, as do most people, that there was no such thing, or that such an antenna was so poor that it was unusable.
Vertical dipoles have some conditions under which they must be used; but once this is understood, they are great performing antennas. The main thing to keep in mid is that a dipole is rather sensitive to its height above ground, and a vertical dipole is much more so. At just over a quarter wavelength in elevation, the signal of a vertical dipole will launch itself out at an angle of almost fifty degrees.
This angle will drop as elevation continues to increase; but will not be at a good angle for local communication until the antenna height is in excess of any tower a normal person has the funds to build.
So the big secret is to keep the antenna height below a quarter wave, or get it up above several wavelengths or more. For eleven meter CB frequencies , this means keep it below eight feet or above eighty. The other problem with a vertical dipole is that unless you are over a perfect ground, there is little or no gain. This is the main reason that most people use a ground plane - that is an artificial ground, when raising vertical antennas.
The other option is to use a tuning or matching stub, basically turning your vertical dipole into an end fed J-Pole. I have J-pole antennas; but for CB it would need to be about 24 feet high. Presently, in the warmer months, I use the old vertical dipole, hanging from the side of my house. In the winter I have a far less efficient indoor antenna which just about fits in my attic. In general, I share the antenna used by my Console V. More details about my solutions to the dilemmas faced by stealth user will be found on that page.
I never have both radios on at the same time. One of the worst antennas I have ever used was one of those little back of the set units. Interestingly, there is not as much loss with one of these as you might think. Since most loss occurs in the feed line, and there is no feed line with a back of set antenna, there is no transmission line loss.
Unfortunately, these antennas are such a small fraction of a half wave that they have an efficiency of only a couple percent. Transmit LED glows red when transmitter is in operation. Lots of mods on these radios - too many. That is probably one of the reasons for their popularity. The following mods are stolen from other web sites, and are all legal, as far as I know. The illegal modifications for transmitting out of band a very popular mod for this radio are not included, though they may be found in various places on the web.
Mike circuit changes: 1. Replace R78 27k with a 56k. Replace R84 4. Transmit circuit changes: 1. Add a jumper in the holes from where you removed D Cut the end of R that is closest to D Add a jumper wire from R the cut end to the banded end of D Resolder this wire to the PC board ground.
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