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Joined: Sun, Jul 16th 2017, 08:15 Roles: N/A Moderates: N/A

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Topic Author Posted On
Power Question jcma05855 on 27/3/19
you might try continuously rotating the pot from end to end VIGOROUSLY ten or fifteen times, and see if that solves the problem. Like anything else mechanical, that hasn't moved for fifteen years, like slide switches, rotary switches, card edge connectors, and tube sockets.
calculation of PEP ? AB3FN on 27/3/19
PEP is simply that, the power present at the instant of a particular "peak" of the speech/RF envelope.

Every speakers voice is different and on "average" contains a different power level. So the same will be true for the "average" power of an SSB envelope. Compression increases the "average" speech power of a signal, while clipping "limits" the peak power.

As Zak mentions FM and carrier frequency shift RTTY are average power emissions, with no variation in amplitude, so the RMS value of each will equal their DC equivalents.

CW, although a constant power level during carrier on, does vary somewhat in average power. Also this affects the power dissipation of an amplifier tube somewhat differently than a SSB signal, which is why there may be a differentiation in permissible power levels.
Pacemaker and power supplies KR6AG on 27/3/19
Have your cardio Doc contact the pace maker manufacturer, and arrange a meet for you and a field rep at the hospital or ??.

I declined getting a pace maker for a couple years, simply because I use both stick and wire welders which generate LOTS of noise and magnetic fields.

My cardio Doc finally arranged a consultation with a field rep at the hospital, and all my "issues" were addressed in 5 minutes. I've had my unit for 5 years now with essentially no limitations for either hobby.
How to Remove Cigarette Smoke from a Newer Solid State Transceiver? WB1GCM on 27/3/19
The answer to effortlessly and instantly removing Nicotine is Ammonia. For the exterior, just moisten a paper towel and wipe it off, or spray and wipe. Either way its gone in a swipe or two.

The plus side of Nicotine is that it is an EXCELLENT finish protectant.

I've used it on literally hundreds of radios, across several years now and it works VERY well. Only two caveats, don't use it on equipment that used water soluble inks on dials, and have plenty of ventilation or do it outside.

For the interior, I often just spray it on using a spray bottle both soft and stiff bristled brushes, while the radio is setting in the sink, rinse it with the sinks spray nozzle then use distilled water to rinse off a second time. This removes dissolved minerals in the tap water. I blow off excess water with compressed air or a leaf blower, then let the unit dry in sunlight for a couple days, or use a few heat lamps.

I have also used a pressure washer for chassis cleaning. Tubes and other water sensitive items removed, transformers not filled with water, and RF can/transformer holes covered with a bit of tape.

Both of the Viking II and National 2-40D chassis were filthy from years of smoking exposure and storage in somewhat pitiful conditions.

The Valiant II took about five minutes soaking with standard pressure washer soap, then a pressure wash. Maybe ten minutes total, max. The receiver I did with Ammonia and brushes and a double rinse. It took about an hour to do.







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