NJDTechnologies

Radio: it's not just a hobby, it's a way of life

Current Operating Frequency and Mode

OFF AIR

I’m not sure why I am so amazed with 630-meter QRPPP but I am

– Posted in: 630 Meter General Topics, 630 Meters

Some time back (described here, actually) I built the GW3UEP VFO/divider/signal source and  a 1-Watt PA into Altoid’s tins for a series of portable experiments that was conducted with Steve, KF5RYI.  I still have aspirations of getting Steve set up with a more permanent antenna for 630-meters, even if very small, so we can enjoy the specific nuance of the WG2XIQ grant that allows the running of two stations from Duncanville, Texas.

Today I was doing some maintenance on the 472-remote grabber, which is located about 1 mile away at my dad’s house, trying to get the brightness and gain set properly in Spectrum Lab .  I recently acquired a new waterfall palette from Eric, NO3M / WG2XJM and due to the late season implementation, the noise level has been sufficiently high that I have been unable to get the levels set properly.  The waterfall is either too hot or too cold.  I need winter to get here so I can enjoy a quiet night to get the levels set properly.

In the process of adjusting, I really needed a weak signal to check my progress.  Firing up the main station was not the answer because it would be gross overkill and not give me a realistic representation at such close range but I remembered that I had the Altoid’s tin based system so connecting that to the auxillary port on the antenna switch and began keying… I guess I should not be surprised:

1W altoids tin QRP to big antenna 042515

The little signal was right where it needed to be and presumably quite audible at the remote receiver.  I would guess that the signal, when using the PA, was probably around 2-4 mW ERP, but perhaps that is hopeful.  I also keyed without the PA, putting a square wave on the coax at levels that were likely fractions of a mW ERP and can be seen more dimly on the waterfall.

So the system does work well, but I admit that the antenna system is also very good.  How it would fare with an 8-foot tall antenna with heavy top loading is anyone’s guess at this point (are you game, Steve?)  It kinda reminds me of being a kid with the 49 MHz walkie-talkies that had the code key where we kids would try to communicate around the neighbourhood.  In this case, it would be a long range reality.