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Why did this 10 meter/6meter Amp us trimer caps on the tube sockets??

Discussion in 'Home Brew' started by ElectronTubesRule, Sep 15, 2011.

  1. ElectronTubesRule

    ElectronTubesRule Active Member

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    So I am looking at an amp that is obviously designed for 11 meter use even though it clearly states on the placard on back that it is for 10/6 meter use.......It is not hideous inside and by Black market amp standards is almost on par with Amateur amps from the same time period. So I like most of this amps design for what it is. The one thing that has me confused is why they have small trimmer caps soldered onto the bottom of the tube socket's???? I have not seen that in any designs of true Amateur style build even on home brew stuff. Outside of this and using ceramic disk cap's in the Pi network everything else is just as you would expect from an amp of this period. They even used Ni-Crome wire with the anti-parasitic instead of copper. It has a nice printed circuit board for the rectifier and the resistors are kept some distance away from the diodes and and all the caps are in a separate spot on the board so their is no problem with the resistors for instance heating up the caps or the diodes and the traces make all the connections that are needed so the parts are nicely separated from each other. It also makes replacing parts a snap because you are not trying to keep a resistor and a diode inpalce across a cap to solder everything in place.

    I have not put her on a dummy load yet and tested her but I am betting dollars to do not's it is tuned optimally for 11 meter and oh also cover's the 10 meter as luck would have it....LOL I am going to guess it will not do well on 6m as it is currently set up since it does not have a band switch to tap the coil at another spot and to be honest I doubt that tiny silver coil will even cover the 6m band. I am positive it has all silver wire for the tank coil. Just about 9-10 months ago I was buying 99.999% Silver by the once for art projects for $21 an ounce and 8ga silver wire for art use as well for the same price by the once and so I am used to looking at 99% silver wire. Given that this amp is 40 years old and the price of silver being dirt cheap back then I am sure this is not silver plated.

    For a single band amp that is 40 years old it is a solid design over all with just a few corner cutting items. They also shielded those parts that should be shielded. They even shielded the driver tube from the rest of the RF energy in the system. It is just too bad they used sweep tubes.



    By the way anyone that is upset at the current price of silver has only to thank those people hording up gold.....All the people that can no longer afford gold have switched to silver driving up the price of silver. As each tax bracket get's driven out of one market they jump to another real hard asset or commodity ie gold, silver, platinum, diamonds etc..... Personaly I wish they could have skiped over silver because that affects my projects!!!LOL
     

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