Further 6J5/6L6 Transmitter Developments

Using my 6J5/6L6 transmitter transmitter in the January AWA OT CW Contest reminded me that my original intent for this transmitter was to have some sort of loading control. In theory L2, the output link, can be wound to properly match a 50 ohm load. In reality I never quite got the power I expected when I used a fixed output link. The solution is to switch to a pi network or add a loading capacitor between L2 and ground.

In keeping with the vintage of the design and the typical output networks of the day I added C10, a loading capacitor, between the output link and ground. C10 is actually a 300pf variable with an old television 300pf doorknob capacitor optionally in parallel with it. The photos show a toggle switch next to the output coil that controls whether the extra 300pf is in the circuit of not. It is needed on 80 but not on 40.

Tuneup is now the standard "dip and load " sort of procedure. Plate current is dipped using C8 and then increased by increasing C10 capacitance. This is repeated until adjusting C10 does not increase plate current. The last step should be to dip the plate current using C8. With a 300 volt (under load) power supply mine easily loads up to about 50mA or 15 watts input.

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How to QSL DX.

HOW TO QSL TO DX:Your card--- Your call sign on the same side of card as the info. Include date and time of QSO CLEARLY. Clearly mark the day and the date-- is 02-06-05 June 2 or Feb 6????. No funny call sign lettering. Keep the "via" call separate from the target call sign. (JAs: could you just print horizontal not vertically?)Your return envelop-- best is a little larger than a post card. Has your complete return address on it with country name spelled out in full in English. Use kind of envelop that has the pull-off strip that covers the glue. Do not fold it, but if you must fold it, do not fold it exactly in the middle. Turn the flap backwards and open. Do not put anything inside your return envelop. Do not mark it for air mail nor anything else--just put your address. Write your call letters on the inside of the flap. Be sure that when the outer envelop is torn open that the return envelop is so small that it will miss the tearing action.Your outside mailing envelop---- Print clearly. Do not seal the flap nor the edges so securely that it takes a can opener to get the envelop open. Believe me, your little sealing and taping job deters NO ONE except the ham who gets your mailing. Leave a little slack in the seal to allow insertion of letter opener or thumb.Inside your outer mailing envelop---- Include your QSL, not attached to anything. Your SAE not attached to anything. Money, not folded and not attached to anything. Covering money with other paper or whatever DOES NOTHING to deter theft--postal thieves are not that stupid, they just tear everything open, steal the cash and throw the rest away (do you think they take time to stop and "candle" your envelop?).Extra tips--- If you just must send an SAE with exposed glue/gum, place the glue strip against the dollar bill which resists sticking better than yourcard, and fold the exposed glue backwards so that it can not be accidentally glued shut upon arrival (Do u know the humidity level in Thailand?).--- Use international reply ENVELOP rather than IRCs. I save IRCs only to send out again like a Christmas fruitcake that does the rounds--they are much more trouble than worth EVERYWHERE in the world. For me, and IRC is a nice but empty gesture.--- Do not send foreign cash to the countries where it is illegal for the receiver to have it.--- Do not send anything except USA cash anywhere unless you are sending local cash to that country--OK example is Franc to France. Otherwise, Small value Francs in Thailand, for example, are very difficult to change to Baht (the exchange fee is greater than the face value of the Franc--for example).---Do not send your domestic postage stamps on an SASE to another country where they are worthless to THEIR postal systems.Overall: In your imagination, go through the steps it takes to handle and answer your QSL request. See if you like it.Meanwhile, I really enjoy TOUCHING and looking at and savoring later real paper QSLs. Real fun, no kidding. 73,Charles Harpole, HS0ZCWk4vud@hotmail.com

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