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That is great news! This device can handle very bad SWR, so it should be difficult to kill. Also take a look at the ARF15xx parts from microsemi, where you can get 750 watts per pill on HF. In all cases, such high power devices need a copper heat spreader on the heatsink. Such heat in...

On HF rigs, you shouldnt need to mess with the VFO. I know you can use a 2.5KHz or 5KHz tuning step mode in SSB, which works well on 11m. At least thats how it is on ft-857d. No more difficult than CB channel knob. Today there is less expensive alternative radio DX-SR8T. mobile HF rigs...

If your goal is talking around the world, you are usually restricted to 1.8 - 30MHz (HF) range. For that, handheld is not an option. VHF/UHF will get you satellites and local. Mobile is marginal at lower frequencies. If ability to take it with you when you move is primary concern, any...

That could be your problem. What hidef said, the balun. Perhaps your antenna doesnt have a good ground plane (the 2nd half of antenna). Could be its trying to use whatever metal antenna is mounted to, and is wasting RF energy where you dont want it.

The cheaper ham rigs dont have good AM, but the better models do. And there is also the new Alinco DX-SR8T at around $550, which could be better rig than IC-718. Would be interesting to know how it does on AM. The 2950dx certainly aint very good at AM transmit, compared to the collector...

Thats a great and useful tutorial. Its important to remember that DX is always there (*), but you need lots of sunspots (or sporadic E skip) to get skip on 11 meters. When the sunspots are lower, you get a maximum usable frequency which is lower than 27MHz. Anybody who remembers what days...

The real russian woodpecker was a pulse at 10Hz. Very short pulse with fast rise/fall, like ignition spark. The sounds you record from CB radios are sweeping in frequency as they are transmitting, and at a faster rate than 10Hz.

You're defeating your first statement with your last statement. But you are correct that power reflected into source transmitter gets re-reflected back to the load. And back again from antenna to load, just like an echo chamber. The only way reflected power wouldnt get back to transmitter is...

I think you are near the truth. SWR is another way of expressing return loss, which is a decibel expression of percentage of power reflected back into the RF source. Standing waves do actually exist. It happens when you have energy of oscillating waves being reflected between source and...

Considering transistor currently in production that can meet the required specifications... Such as 2SD882, is the same NPN with sufficient voltage and current ratings for the power level to 50ohms. And transition frequency sufficiently high enough for CB. But the package is slightly...

TO-220FP has no metal around mounting screw. Only metal is on back mounting surface. TO-220FP is for application requiring that case be electrically insulated from heat-sink. TO-220 has better thermal dissipation, but requires a plastic washer for screw when it must be insulated from...

It should be. The requirement is to match or exceed the required specs of 1969. Such as collector-base voltage, collector current, transition frequency at least three times CB frequency, and desired power dissipation. The package needs to be TO-220 if drop-in is required. Thats why...

36volts must be for a forklift charger. battery chargers are not power supplies. They're not regulated the same way.

how about a modat unit ID, you'll sound real official... Selcall - Wikipedia, the free encyclopedia

Thanks for the product comparison. Looked into the KPA500. Someone wanting basic features will go for Ameritron to get the best dollar per watt. But the Elecraft has some interesting features: Automatic band change via high-speed RF sensing, switches very fast. Accurate 3-color LED power...

I need to wonder how much harmonic problem really exists. Has anyone ever heard signal from somebody transmitting on a lower band than you're receiving? I'm sure it can happen, but has it really happened, or is it common. HF Ham bands were selected so that most harmonics on lower bands will...

vocaline information Vocaline JRC-400, JRC-425 according to this: 27 Megacycle History in the U UHF CB languished for about ten years, then it was killed when 27MHz CB became available in 1958. UHF radio really didnt comercially exist in the 50's. PLL circuits werent in production...

In this pdf (a few pages in) you can see original vocaline UHF transceiver. The poor frequency stability of these units shows why lower frequencies were chosen for CB, due to 1950's technology. http://k9sth.com/uploads/restored_equipment.pdf

If you want somebody to give you a signal report from a transmitter with such a large dead-key to PEP ratio such as 2w to 122w, then you need to give them some continuous audio to allow their S-meter to react. Otherwise when you talk their s-meter may not be able to swing fast enough to the...

For AM signal, you want negative peak compression so the RF power doesnt get pinched off to zero. Because thats where the splatter comes from: the abrupt switching of RF power. Usually this negative peak problem is from the CB transmitter, and any amplifier after that will just make all that...