Getting on the air. April 17, 2008
Posted by n9ik in operating, portable, station.Tags: blt, cw, keys, portable, qrp, rockmite, station
2 comments
I finally got an antenna in the air temporarily this afternoon, and got out my RockMite 40, BLT and Nye Master Key. The 40 meter band seemed very active; at least there was lots of activity around 7.030 MHz, which is the frequency of the crystals currently installed in the RockMite. Everyone that I heard was a bit fast for me; I was able to copy only about 15% or 20% of what I was hearing.Most of the calls that I was able to copy were in 4-land. One person was having a ball with his “bug” slowed down to about 15 wpm – I forgot to write down their call, but they had a very distinctive “fist”, with comparatively long dashes.
The photo above shows my portable station: Battery pack with 8 “AA” cells, RockMite transceiver on 7.030 MHz, Nye-Viking Master Key (model 330-001), NorCal BLT (Balanced Line Tuner) modified to also tune unbalanced feed lines, and my cheap, worn-out Koss UR/29 headphones. The BLT is feeding a speaker-wire doublet as an “inverted-V” with the apex up only about 25 feet or so. The tuner handled it easily.
BLT Construction September 6, 2007
Posted by Thor in operating, portable, projects, qrp.add a comment
Well, I finally got around to completing the BLT – Balanced Line Tuner. It’s not just a balanced line tuner though; it now will tune a coax-fed antenna, and a random-wire antenna, as well as a balanced-line antenna. It was pretty simple to put together, although I had trouble a couple of times, caused by my shakiness. Following are some photos of the building process.
Tinning the PC Board
T1 core
T1 secondary winding (wind this first)
T1 completed
T1 mounted on PC Board
The completed PC Board
L1 wound on core. L2 & L3 are wound on the same core
Completed PC Board and Toroid (L1 L2 & L3)
Front panel connectors
Rear panel connectors
Wiring the panels
Completed. Front view. Crappy paint job.
BLT completed. Rear panel. Crappy paint job.
BLT Kit arrived. August 28, 2007
Posted by Thor in portable, projects, qrp.add a comment
Well, the BLT kit finally arrived yesterday. Yippee! I did a parts inventory last night, and found some discrepancies from what the documentation says should be there.
- R4=1 K ohm 1/4 Watt resister. Received a 410 ohm resistor.
- 4 rubber feet. Missing.
- 8 1/4″ x 4-40 undercut flathead screws. Missing. But, I think this is due to there being a different enclosure than shown in the docs.
A couple of other gotchas:
- The enclosure is different from that pictured in the documentation. It is a little dirty and is scratched from the bending process.
- The PCB has “hair” – fiberglass fibers at least an 1/8th inch long – along the edges. It needs to be sanded off.
A good plus:
- The extra parts are included and the enclosure is already drilled for the “mod” that adds the ability to use a coax feed line or a balanced line antenna, and not just a balanced line feed. Great! I was planning on doing this mod anyway.
It turns out that aside from the missing rubber feet, I do have all of the appropriate parts. Here’s what Doug said in his email to me:
Thor, the parts list has not been updated to match the new enclosure. The 70 ohm resistor is an improvement over the 1K as it makes the LED righter and easier to see.
By the way, the price is going to go up on the kit soon due to the improvements and additions of the switch and the extra BNC. Also the new case is bigger and easier to work with. Please let me know what you thin of the changes.
Thanks Doug
As for the case, I think I’ll paint it anyway, and I can easily find appropriate rubber feet locally. And if I didn’t paint it, it would probably get pretty beat up looking in time anyway, since I don’t exactly use kid gloves with portable gear. I look forward to getting this kit built and to put it to use. Updates to follow.
Rock Mite 40 Complete August 22, 2007
Posted by Thor in portable, projects, qrp.6 comments
I’ve finally gotten around to completing the Rock-Mite 40 transceiver kit. It was fun to put together, in spite of my problems with my shaking hands and the difficulty it causes with putting components and wires on the board and connectors. Below are a few photos:
The RM board is fully “stuffed”, waiting for wires.
In this picture of the RM at board level, you can see that I’ve used SIP sockets as sockets for the crystals, allowing me to change out the crystals with 7.040 MHz crystals, which are for the other 40meter QRP calling frequency.
Another board level close-up.
Here some of the wires have been added. The crystals have been removed, and you can clearly see the SIP sockets at lower left and upper right on the board.
To fit the FCC’s newer (June 2004) spurious emission requirement, a 150pF cap and a 3.3 uH RF choke should be installed in series between the center conductor of the antenna connector and the board. The RF choke lead would not fit through the through-hole on the board, so I soldered it directly to the antenna connector, and put the capacitor on the board. The antenna connector and the caps position on the board are close enough that the leads of the choke and capacitor can be soldered directly together with out using the coax. Eventually, I ended up breaking the lead off of the choke, and since I don’t have a replacement I removed it and the cap and used coax to connect the board to the antenna connector. I’ll put the choke and cap back on when I can.
It’s a tight fit with the board and connectors all wired and installed in the Mighty Box enclosure. Here you can see that the leads for the two crystals (lower left and upper right) needed to be bent over so that the crystals would fit. If they had been soldered directly to the board instead of using sockets, they would probably have been fine standing up straight.
Ready for the bottom cover to be screwed into place.
Front view of the completed RockMite. Left to right, audio gain, switch, phones. The switch is used to toggle off-set frequency and control the internal keyer.
Rear view of the completed RockMite. Left to right: key, antenna, power.
If/when I get a clear label cartridge for my Brother P-Touch labeler, I will add labels to the RM case.
Now, to make some contacts!
BLT Delayed August 3, 2007
Posted by Thor in portable, qrp.add a comment
I’m bummed. I ordered the BLT (Balanced Line Tuner) from Hendrick’s QRP Kits five or six days ago, but I didn’t notice that they would be closed until August 10th. Oh well, another couple of weeks wont kill me… will it?
Rock-Mite update July 30, 2007
Posted by Thor in portable, projects, qrp, station.add a comment
The Rock-Mite transceiver kit that I ordered arrived in today’s post. I’m anxious to get it built and to make my first QSO (contact) with it. I would have built it tonight, but I’m out of solder, and need to go shopping for a few things.
Speaking of shopping, I ordered a BLT kit tonight. No, not the kind you make with bacon, but the tuner used to tune balanced line antennas.
So, my portable & QRP rig will be made up of the Rock-Mite, a BLT, a doublet antenna and, if I can find one locally, a 7 amp-hour 12 volt battery.
The Mity Box, mighty fast July 23, 2007
Posted by Thor in portable, projects, qrp, station.add a comment
Very fast service from American Morse Equipment. I ordered the “Mity Box” enclosure for the “Rock-Mite” radio from them on Friday, and it arrived with today’s mail. It’s a beautiful little enclosure, CNC milled out of an aircraft aluminum billet, and anodized blue. All the holes for connections and controls are pre-drilled; it’s completely ready to mount the board and chassis-mount components.
Another seven months gone by July 9, 2007
Posted by Thor in operating, portable, station.add a comment
Yes, another seven months of no activity in ham radio. I still have a broken antenna (Butternut HF-9Vx) on the roof (I don’t own a ladder, can’t afford to buy one, and am too weak to climb up from the deck railing), my gear, what’s left of it, is all still jammed into the back of the overcrowded garage, and it is still difficult for me to remember tech stuff, and to figure things out anew after those brain treatments that I had a few years ago. That’s really a bitch, because these things used to be so easy for me. I think that I just need to get motivated to relearn this stuff. Time to break out the books and take some practice tests. At this point, I’m embarrassed to admit that I have an Extra class license. I’m not sure if I could pass a Novice/Technician class exam today, let alone the Extra test.
I’m glad now that I did not succumb to the urge to sell my Kenwood TS-130S rig a while back. Not only is it my only QRO radio now, but it’s my first rig, and more importantly, is also my mother & step father’s first rig. It has a history. It survived life cruising aboard a 45′ sail boat, covering the west coast of the US and central America to the Panama Canal, and in the Caribbean, both in use and in a storage space after being replaced by a Kenwood TS-440S. It even survived the sinking of the boat at the island of Culebra during Hurricane Hugo in September of 1989. Fortunately, the radio was well-wrapped in plastic bags at the time. The 440 wasn’t so lucky.
Let’s see now, I have the TS-130S, but no power supply, battery or otherwise (I’ve almost always operated by battery), no permanent antenna, no space to speak of, although that may change soon if one of my sons really does move out. I do have wire to make antennas with, and can string ‘em up between the house and a tree in the back yard, although anything that I could put up would be fairly low. Vertical might be best, but experimenting is half the fun.
Oh yes, I almost forgot that I do have a couple of QRPp rigs to play with, but my code copy and sending are awful. As with my tech knowledge, I’m not sure if I can copy or send much more than the five wpm that I passed while taking my Novice test. One is a FOX3 that I remember having a few QSO’s with, and a Tiny Tornado or two (say that three times fast!), still unassembled, several unassembled Pixie2 kits, and a few various and sundry accessories, some in the ubiquitous Altoids tins. 
I still very much regret selling the Elecraft K1 that I built five or six years ago. I sold it at a time when I thought that the money I could get for it would make a difference with our financial situation at the time. Needless to say, I was not thinking very clearly at the time; a result, again, of the treatments that I’d been having. Oh, well. Building a new one is something to look forward to when I can afford to buy a new kit!
Oh! I just remembered that I have a DK9SQ Vertical Loop antenna. I do need to get a new mast to use it on though, the one I had was damaged by the USPS. The mast that I had was the MFJ-1910, but I think I’d want to get the DK9SQ model to replace it, it seemed stiffer, the pieces locked together better, and seemed stronger overall when I had the chance to examine one at a ham fest a few years ago. Then again, I see that MFJ now carries slightly taller fiberglass models with locking clamps or hose clamps to lock the segments together. That’s a consideration too, though not for the DK9SQ loop.
The photos above show my portable configuration at one time. When I took the pictures I had been operating outside on my deck with the Elecraft K1 and MFJ-564 iambic key (definitely not a portable item). The antenna shown is the DK9SQ; the middle photo is with the antenna all packed up for travel – MFJ mast on the left, the horizontal spreaders to the right, and the antenna balun housing with the wire wrapped around it on the floor. The photo to the right shows the antenna up and ready for work.
