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To go on about the antenna, the current is the main parameter that radiates the energy into the surrounding meduim. On a base loaded shortened antenna, the current is the greatest at the base above the loading coil and tapers off up the whip to 'near' zero (low value) at the top. Other...

Lets try this all again. There are TWO conditons possible in an antenna 'system' that includes the antenna AND the transmission line (known as the coax). 1. With a perfect match between the transmission line and the antenna there is no reflected power (known as SWR). Therefore the coax length...

....How about looking at the theroy behind all this for the correct answers. ....If the antenna is the correct match to the feed line (at the operating frequency), the feedline length makes no difference except for loss over it's length. ....If however the antenna is not a match, reflected...

For those who 'have done it', you lucky. No regular supplies are designed to just connect togather unless one is designated as the control and a control line is connected to each. Here are some reasons why; They must load share equally or one tries to provide the larger current it was not...

You see how little you really know there BM. I've seen your silly threads on other boards. Please, stay here and give the rest a break! As for the AL80, now you know a 'little' more about it than you did before. Reason I replied as I did was because there was a number of things left floating...

There is still something left out of all this. If referencing an AL80 amplifier; it is only an amplifier not a plate modulated stage. In cathode drive, the driving power minus losses is passes on through and adds to the 'amplified signal' developed from grid modulating current flow from the DC...

I know your not circuit savvey but SSB is a balanced 'null' circuit that is adjustable for that null. If this adjustment is shock sensitive or a circuit board solder joint has become intemittant, or the pot has become intermittant, a carrier will result in SSB mode. This is how AM is...

AND BTW, a Fla. CBer got cought with illegal radio, first amp driving a second amplifier and they were still warm to the touch when the field engineers came if for inspection. Can you say $10,000 notice of libality? Once any non CB authorized equipment is used in any form, the legal ability to...

From my perspective it's good there is an ARRL. .....I think they have to much to cover with the people they have and the money to work with. .....It seems they are nearly totally involved in defending an amateur right to erect antennas and towers, saving the bands from commerical intrusion...

Two 2897s are good for about 200 watts peak output. Depends on the input as to how much drive is needed to get full peak output and stay clean. The rule on AM is for 100 percent modulation the carrier power will increase 4 times for peak power. That is for 200 watts peak, you cannot drive...

Wow, a look at the photo shows absolutley no DC power regulation and no output filtering whatsoever.

Class C is never advised for any AM or SSB operation, only FM. The class of operation in usually not understood be the average user. For AM use, class AB or AB1 is good enough if the amplifier has a Linear portion to it's operateing dynamic range. Class C has the amplifier cut off such that...

If the antennas is matched to the coax 50 ohm impedance and there is a valid ground plane in place to effect that match, then under these conditions there will be no 'common mode' outer shield current to have any effect by coiling the coax. You need to understand that in a closed system like...

It seems in this thread, that the FCC harmonic output limits and IMD (inter modulation distortion) limits are being ignored for marketing these amplifiers. They need to be tested for approval by the FCC or are illegal to market in the US, made here or imported. Running untuned inputs and...

The article is about the following; 1. Setting the filliment voltage of a 3-500 to 4.8 volts using a dropping resistance in the mistaken belief it will extend the tube's life. 2. He measures the voltage at the dropping resistance instead of at the tube pins and with an incorrect AC meter yet...

To add some updating to this thread, ....I use a w2ihy 8 band with a Heil HM 10 on boom and the new Heil Pros Set Elite with HC6 element. ....Kenwood TS480 Eq on flat. ....IHY output gain set up to satisfy ALC requirements first then compression second to about 6 db compression point...

Hello Denis, You have the same class ticket. How's come the band info was not part of his test study? It's the main purpose of getting the ticket and not so much the tech of it. Both of you have the same privledges. CW on a part of the 80m band, the 40m band the 15m band and cw and usb on...

I have TELSTAR 6M that had a single 4cx250f 26 v heater version. I replaced it with the Russian GS36B said to be very simular the the Eimac 4cx400 or SEVETLANA. It's a direct plugin. The change over consisted of installing an extra 6.3 vac heater transformer on top of the original 28 vac...

Interesting collection of responses. Some idicate total; lack of knowledge. First, if you key in my call on the internet it will show a lot of info I have no control over, where I live, maps and the whole nine yards. Once you get a lisc, the whole world knows where you are and much about...

If you want to follow the letter of the law there is more to this than just the harmonic filtering. The devices used should have low intermod distortion and not be driven more than about 80% of the available output. You must know that 12 volt devices don't have much head room before RF...