The Pixie Rides Again!

By JonathanGuthrie, 26 August, 2018

Well, after thinking about it, and using all the tools at my disposal, including colorful language, I managed to get the old S8050 out of the S-Pixie kit. Now, I've been buying component assortments for years. I figure that if I want to build my own equipment, especially equipment of my own design, I'll need parts and it's better to buy cheap assortments well in advance than to order the specific parts that I think I want. I mean, the fact that I have, say, an S8050 transistor, that can guide my designs to use parts that I have rather than be overwhelmed by all the parts that there are. Anyway, I've got a bunch of transistors, diodes, resistors, capacitors, and, now, fixed inductors.

I found out that, due to ordering things with long lead times from China, I actually have two assortments that contain S8050's, and I already had one open, so I just put the other S8050 in from that one. This time, while making measurements, I was careful to not hold the key down too long. The power output is about 900 mW, more than I remember with the original transistor, and it looks like a good sine wave at 7.030 Mhz. Success!

After thinking about it, I also hooked up the radio to an antenna in an attempt to test the receiver. However, the bands are deader than doornails. Something about a solar storm wiping out ionospheric propagation. Dangit! I did hear noise, and what sounded like human voices, which doesn't worry me so much as it's a direct conversion receiver and the oscillator is at 7.030 MHz. I'll have to try it when 40 meters isn't completely dead.

Anyway, I need to figure out how to tune my antenna without driving it from the transmitter. I don't expect either the Pixie or the Peaberry to be too willing to drive a load with a high SWR. Since my crappy attic antenna relies upon the use of a tuner to make the load reasonable, that means I have to tune it before I put the transmitter on. I've written down approximate settings, but sometimes they aren't right. I haven't yet figured out why, which is another problem for another time. (Actually, I think I need to go up in the attic and solder all the connections together and stuff like that. I know I need to replace the air-core "balun" loop with something wrapped around the ferrites I bought for RFI amelioration. But...It's August in Houston, so who wants to go up into the Hell of an attic to do work? Not I, is who. Especially since my ankle is busted right now.)

Aaaand, that's where I am! At a place where I have several radios I can use. I just need to get one on the air.

JonathanGuthrie

5 years 5 months ago

Okay, I've been messing with it, and even connected the transmitter to the antenna. The problem isn't the antenna, it's the tuner. Something's wonky inside the TenTec Model 238 antenna tuner that I have. Moving the knobs causes major jumps in the SWR. I get much better luck with the Dentron JR tuner that I couldn't sell from Don's estate sale. I suppose I could dig out my MFJ-969 tuner, but that thing was such a horrible experience to use that I'd rather not.

Eventually, I may have to fix the TenTec, but this'll do for now.

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