Tinkering

[w8cbc]

The latest one-night project is a 100-watt dummy load, just completed.

I stumbled across a substantial 50-ohm carbon-film resistor today. Used, in the junkpile. Ah. Possibilities immediately suggested themselves.

First thought was to tie it to a piece of RG8 with a PL-259 on the other end. I made a 20-watt dummy this way awhile back. Then I started looking for a box to put it in. One thing led to another and I wound up cutting, bending, and shaping some perforated aluminum stock into a 2"x2"x8" box. A SO-239 went on one end and I bolted the ground end of the resistor to the box. Connected everything solidly. Closed it all up nice and neat and brought it home to test.

Perfect 1:1 up to 20 metres. Then I get a bit of reflected power - still not terrible, 1.4:1 at 29 MC. It took three minutes at 100 watts to really heat the thing up. I declared victory and put the thing away.

A few minutes later, I got it back out and bolted a processor fan to the rear end, blowing outward so's to draw air through the tubular resistor. Thought about running the fan from rectified RF, figured out the resistances involved, and concluded that I'd spoil the match so instead I wired up a DC connector for the fan and plugged in the miniscope's supply. Ran 100W into it for several minutes at 21265 KC. SWR stayed below 1.2:1 and the fan was blowing warm (not hot) air.

So, something I'd considered buying wound up being an enjoyable and fairly simple project instead.

[kb3mng]

Isn't it way cool when you do something like that? That's what amateur radio is about for me.

I just made a 10-or-so watt dummy load with a tap to measure the RF voltage. It is a regular resistor array with a 10k resistor into a half-wave rectifier. Plug a voltmeter into it to get a reading. (As long as the RF voltage is high enough to make the diode conduct, that is.)

I ordered a bunch of 300 ohm 2 watt non-inductive carbon film resistors from Digikey, and the entire batch came out at 294 +/- 1 ohm. I used the 6 highest values, so now I have a nice 49.1 ohm dummy load. If I get a few resistors that come out a little high someday, maybe I'll replace a couple and get a better match.

Apart from cramming everything into a tiny box I had available, the most entertaining part was soldering a surface mount PIN diode. There is no board in the dummy load, so I have an SOT-23 package (about 1mm X 2mm) just hanging between the leads of a regular size resistor and capacitor.

I don't remember the SWR, but it was less than 1.5:1 on 6 and 2 meters. (That's the magic number that the manual for my handheld says to stay below, which is why I remember it.) I built my power/SWR meter from a kit, and it doesn't give correct readings for UHF, so I'm not sure how it is at higher frequencies. I keep thinking I should try to make a better winding on the directional coupler in the power meter, but I'm building an antenna mount that has higher priority at the moment.

I've built a few things with surface mount components now, and it turns out not to be nearly as difficult to work with as I expected from what I've read. Of course, I'm not talking about BGA packages or TQFP, but the larger tiny stuff is working out ok for me so far. http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif

[N8CPA]

Do you really wanna know what I'M building?

Everybody knows--I've certainly not stopped posting about it--I'm approaching the end of a major antenna project. Sometime last spring, I started wondering if a receive only antenna might help me hear some of those rare ones to the west. So I experimented during Field Day. I interconnected a separate antenna to my 735, using a Radio Shack A/B switch to select between transceiving and the separate antenna. It was such a success, I decided to have a semi-permanent RX antenna by the following NovSS. I spent part of the summer and fall researching RX antennas. Lacking space for a beverage, I decided to build a variation of a Kaz, a small, ground independent, vertical delta loop.

I decided on the Kaz because I intended to mount it over the length of our above ground pool--the only space available during fall and winter--and the horizontal portion of the Kaz is exactly the length of the pool deck, 40 feet. The height will be 10 feet over the winter cover of the pool. The peak of the delta will be suspended "trolley" style over the middle of pool from a cord
stretched between 2 DK9SQ portable masts. The antenna will be removed during swimming season.

Other parts of the project are improving the grounding and lightning arrestor system, performing intensive maintenance on my R-7, and improving the apex angle of my homebrew VEE, aka
"Awkward-L."

The project began around the first of the month when I ordered ICE arrestors to replace the Transitraps I have used since Chris and I moved in here 11 years ago. As soon as they arrived, I brought the arrestor box into the house and began drilling holes for the new arrestors. When they were securley bolted, and when the ohmeter read continuity among the housings of all the arrestors, I reinstalled the arrestor box at the feedline entry point of the house. I also replaced the #8 (or #10) ground wire from the arrestor box to the ground rod with 1/2" wide flat, braided strap. And phase 1 was complete.

Phase 2 began when I decided on a more complex RX antenna switching arrangement for the IC-735. In addition to antenna switching, I wanted to be able to separately tune received signals. So, I interconnected an unused MFJ-941D to the IC-735.

The explanation is far more complex than the connections.

Imagine the back of the 941D. There are 4 SO-239s labeled XCVR, Coax 1, Coax 2, and Bypass. There is also a 3 banana plug terminal for a wire antenna connected to an internal balun for either a single wire or a balanced antenna, and a grounding lug. On the face of the 941D is a selector knob with settings for Bypass, Balun, Coax 1, Coax 1 direct, Coax 2, Coax 2 direct. 3 additional knobs to adjust capacitance at the tuner's input and output, and to select a value of the inductance.

The back of the IC-735 has three antenna routing terminals: An SO-239, and 2 RCAs. One RCA is parallel to the SO-239 and labeled "ANT OUT," hereafter to be called "RCA 1." "RCA 2" is labeled "RX ANT" or "RX ANT IN." When transmitting, an internal relay connects the signal to the SO-239. When receiving, the default state, the relay engages RCA 1. A short, shielded RCA cable is provided with the rig to jump from RCA 1 to RCA 2 when the same antenna is used for both transmitting and receiving.

I have connected the 735's RCA 1 to the 941's Coax 1 SO-239, using a shileded RCA cable and PL-259/RCA adapter. A similarly adapted cable runs from the 941's XCVR SO-239 to the 735's RCA 2. I currently have a mobile antenna connected to Coax 2 on the 941, just for experimentation. Later, the "Kaz," will be connected there.

The IC-735 is connected via its SO-239 to a matching autotuner (AT-150). By rotating the selector on the 941 I can select to have the received signal pre-tuned by the AT-150, and manually fine- tuned by the 941 using the COAX 1 position. I can reach over and turn off the AT150 to tune the received sig only through the 941 in that same setting. I can select COAX 1 DIRECT with the AT150 off to hear raw signal, or I can turn the AT150 on to tune it there.

When I connect the RX antenna, it will only be tuned through COAX 2 of the 941, having its own feedline completely independent of the AT-150. By selecting COAX 2 DIRECT, I'll have raw signal.

Eventually, I will install an indoor antenna via the WIRE BAL connector on the 941. I'll then have yet another receiving option for stormy days. [Let's see: I haven't been in the attic lately. Maybe I can climb that ladder when my wife isn't around to freak out--HMMMMM.]

Yesterday, I finally attached the wires of the Kaz to the terminating transistor and wound the antenna on the wire's (leftover 18ga. speaker wire) spool. I've already wound the 9:1 balun. Today, I'll finally get it installed. And, since it's not raining, I'll finally get the R-7 back on the tower [telescopic, fold-over is the only way to go!] By this evening, I'll have that separate RX and TX capability, the idea of which began this frenzy, this Oktennafest. And on Saturday, a few people are coming over to finish the project with a ceremonial re-hoisting of the Awkward-L to be followed immediately by the consumption of mass quantities of dogs, burgers, and libations! [HMMMM--weenie roast!]

Welllllll, you asked! http://www.qrz.com/iB_html/non-cgi/emoticons/tounge.gif

[wb7dmx]

I just finished building a curtis keyer code pratice ocillator to play with my bencher paddels, hope to learn how to send with it before I connect it to my rig,
maybe some day I will increase my code speed a bit,
I have ben using a stright key and this is really differant.

[w5alt]

Well, I built a 30m QRP TX (to go with a 30m DC RX I already had) and a 40m software defined reciever so far this week, both from kits.

Antennas are a continual project here ...

73,
Walt, W5ALT

[K9YLI]

field day project. Mulling over a way to use a small stereo amp,so two people can use head sets.
feed recv audio to both channels.. pick up some talk audio and feed to just loggers headset on one of the stereo channels to hear outgoing audio. person on mike wont hear themselves on head phones. use mono phones on each channel..
just a toy...
k9yli

[w8cbc]

This wasn't a project so much as a sudden bit of "Oh, yeah, that's it".

I got into the 751A a few weekends ago to retune the BFOs to spec. They were all off to some degree, LSB especially. Well, I couldn't get the LSB to quite line up but did get it within 50 Hz by removing the tuning slug entirely. Decided that was good enough for the time being and put it back together.

A day later I remembered something. Took it apart again and clipped an appropriately-threaded brass screw to length. Screwed that into the LSB BFO coil as a replacement slug and adjusted until it was bang on.

As iron / ferrite will raise inductance in a coil, brass will lower it. So I don't have to replace the drifted cap in there after all.

[n8yx]

Couple repair projects underway...a Drake R7 and a few HW5400s which I'm going to sell as soon as they "check out". Also going to replace the final transistors in one of my Cubic Astro 103s over the holidays.

On the building front:

1) A TX/RX/RX VFO controller/wattmeter/antenna switching console to match my Yaesu FR-101/FL-101 line (2x RX controlled by one TX).

2) 2x 3-500z in a big Bud swing-top case; gotta find a suitable HV transformer and some other pieces/parts. When done, it'll look similar to a TL-922.

3) A DDS VFO arrangement for the Drake 7-line. Not an external box; I'm looking to design a PIC-based unit which will replace the existing PTO assemblies...in form, function and so forth.

4) Antennas - many. Almost all of my station's antennas have been taken down for R & R; currently have a 5BTV, A-99 and a 75/17m dipole up in the air. A new tower was -supposed- to go in this year...but the pieces sit in the garage, waiting for me to finish the base.

[kl7aj]

Quote[/b] (kd8bsr @ Oct. 25 2005,21:56)]The latest one-night project is a 100-watt dummy load, just completed.

I stumbled across a substantial 50-ohm carbon-film resistor today. #Used, in the junkpile. #Ah. #Possibilities immediately suggested themselves.

First thought was to tie it to a piece of RG8 with a PL-259 on the other end. #I made a 20-watt dummy this way awhile back. #Then I started looking for a box to put it in. #One thing led to another and I wound up cutting, bending, and shaping some perforated aluminum stock into a 2"x2"x8" box. #A SO-239 went on one end and I bolted the ground end of the resistor to the box. #Connected everything solidly. #Closed it all up nice and neat and brought it home to test.

Perfect 1:1 up to 20 metres. #Then I get a bit of reflected power - still not terrible, 1.4:1 at 29 MC. #It took three minutes at 100 watts to really heat the thing up. #I declared victory and put the thing away.

A few minutes later, I got it back out and bolted a processor fan to the rear end, blowing outward so's to draw air through the tubular resistor. #Thought about running the fan from rectified RF, figured out the resistances involved, and concluded that I'd spoil the match so instead I wired up a DC connector for the fan and plugged in the miniscope's supply. #Ran 100W into it for several minutes at 21265 KC. #SWR stayed below 1.2:1 and the fan was blowing warm (not hot) air.

So, something I'd considered buying wound up being an enjoyable and fairly simple project instead.
Funny you should ask. I was just rummaging through a parts drawer and found on old Collins 2.1 KHZ mechanical filter. At first, I thought it would somehow be immoral to use such a venerable relic...it deserved a place on my vintage parts display shelf. Out of curiosity, I decided to build a little oscillator to see how the thing worked...of course it worked fine. After staring at it for a while, parts mysteriously started accumulating around it, most notably, a Minicircuits DBM I happened to have for another project. Somehow, an old mic preamp card materialized out of nowhere, and attached itself to the IF port of my DBM. Before I knew it a single-sideband modulator evolved. I imagine before the week is out, I'll find that the thing has assembled itself into a single sideband transmitter. I just don't know how these things happen. http://www.qrz.com/iB_html/non-cgi/emoticons/sad.gif

eric

[W9AFB]

The plan for over Thanksgiving break is to modify an old CB board to a six meter beacon radio. Hopefully all goes as planned as it would be really nice to get the beacon back on the air!

[WA5VQM]

This week I'm re-capping a Drake AC-4 power supply to go with my recently revived second T4X transmitter.

A couple of weeks ago put up a homebrew 20M vertical.

Also pulling together plans and parts for a 30M transmitter.

http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

[K9STH]

I just got through eliminating the "warble" from the LMOs in my Heath SB-301 receiver and my Heath SB-110A 6 meter SSB/CW transceiver. Over the years the lubricating grease dries up in the unit and you have to remove it from the equipment, disassemble it, and then clean out the old grease.

It isn't hard, just a pain in the posterior. Also eliminated a problem in the SB-110A that has been present since I first obtained the unit over 30 years ago. The frequency shifted about 150 Hz between transmit and receive. This was due to the shifting of the sideband offset bias that causes the calibration to be the same on both upper and lower sideband. I finally had to lower the bias voltage and use a zener diode to hold the bias at the same level (it had been shifting about 0.7 volts - from 72.2 volts to 72.9 volts. Finally got everything stable at 43.0 volts. Did have to move the dial almost exactly 1 KHz to compensate for the change in bias. However, now no shift in frequency.

Glen, K9STH

[WA9SVD]

Got a gazillion projects started...

AH, but to finish! Aye, therein lies the rub...

Finishing a PSK interface box, repairing an age-old TTL digital clock, (display finally went bad) fixing another digi-clock/thermometer. All simple homebrewed stuff, but time consuming. I always thought LED digital displays were supposed to last a lifetime. If that means only 31 years, I'm living on borrowed time..

[KI4FCP]

all mime are antenna projects, Im building a 5 elm 6M beam from assorted parts givin to me by a local and the other is my Homemade 40ft crank up tower made from a Lighttower boom and pulleys. Mybe by spring ill be ready to get it done. http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

[kl7aj]

Looking through my 1926 ARRL Handbook, I've gotten a sudden hankering for building a good spark transmitter. Does anyone have some sheets of mica so I can build some good capacitors?

eric

[n8yx]

Quote[/b] (kl7aj @ Oct. 26 2005,15:27)]Looking through my 1926 ARRL Handbook, I've gotten a sudden hankering for building a good spark transmitter. Does anyone have some sheets of mica so I can build some good capacitors?

eric
I'll send you some mica capacitors... http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

[w8cbc]

7aj - funny you should mention the Collins mechanical filters. I have a trio of 'em, just begging for attention. Hmmm...

I think the next mod will be to the ever-changing Antenna Tuning Contraption Number Three. I got 'hold of a twin-stator air variable and will put that on the antenna end per a design I found in the ARRL handbook. It should, in theory, give me more low-end tuning range, as well as eliminating the high-pass characteristic at high impedance. I'm not sure I like the higher Q that'll result though. I suppose I can put in another switch, to take out the C-to-ground leg when I don't need it and thus restore the present characteristics.

A long-range project is a sequenced T/R switch for the Apache and R392. All I need is to find a few good, heavy relays and I'm set.

[WA2ZDY]

Quote[/b] (kl7aj @ Oct. 26 2005,18:27)]Looking through my 1926 ARRL Handbook, I've gotten a sudden hankering for building a good spark transmitter. #Does anyone have some sheets of mica so I can build some good capacitors?

eric
Leyden jar condensers. A jar with tin foil wrapped around the inside and outside as the plates. That's how I learned to do it.

Come to think of it, I learned a lot of stuff from old guys like W2OJJ, W2DED, etc, who were on the air when King Spark ruled the ether. OJJ got me my start and DED gave me a box of 4D32's back in 1975 when they were already on the way to being unobtanium, and expense as all get out at that.

[k7mh]

An amplifier for my QRP rig that will have a 6AQ5A driving a pair of 6146's that drives a pair of 3-500Z's that drives a pair of 4-1000A's. The power supply is going to be a real bugger! http://www.qrz.com/iB_html/non-cgi/emoticons/tounge.gif

[KG6YTZ]

Maybe I should post a pic or two of the Frankenbracket that now supports my IC-2100H. http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif

[k6pme]

My winter project: Elecraft K1-4 and tuner with multiple power sources, (ni-cad, solar, AA batts, external 12VDC) and antenna configurations, (1/4 verticle, resonant dipoles, random wire) All to fit into a "briefcase" type aluminum toolcase, including antenna's.

Current status is the inventory stage of the Elecraft. Hopefully it will be complete and operational by field day 2006.

[kl7aj]

Quote[/b] (kd8bsr @ Oct. 26 2005,19:45)]7aj - funny you should mention the Collins mechanical filters. #I have a trio of 'em, just begging for attention. #Hmmm...

I think the next mod will be to the ever-changing Antenna Tuning Contraption Number Three. #I got 'hold of a twin-stator air variable and will put that on the antenna end per a design I found in the ARRL handbook. #It should, in theory, give me more low-end tuning range, as well as eliminating the high-pass characteristic at high impedance. #I'm not sure I like the higher Q that'll result though. #I suppose I can put in another switch, to take out the C-to-ground leg when I don't need it and thus restore the present characteristics.

A long-range project is a sequenced T/R switch for the Apache and R392. #All I need is to find a few good, heavy relays and I'm set.
I still think a reversible low-pass L network is the best antenna tuning contraption. Conjugate match theory tells us that you match ANY impedance to ANY other impedance with no more than two components. You might need a real BIG component under some circumstances, but it always works. I can't for the life of me understand why so many manufacturers crank out tuners with a HIGH PASS t-network. I always thought a tuner was supposed to SUPPRESS harmonics. I'm appalled.
http://www.qrz.com/iB_html/non-cgi/emoticons/sad.gif

o well


eric

[w8cbc]

To be honest, I think much the same thing. I had two hefty variable caps and a 20-amp rotary coil and made 'em work, which was the important part at the time. If/when I get 'hold of another rotary coil, believe me, it'll get changed around to a low-pass T. For now, I'll use the split-stator as C2. It'll be bandpass at least. Just so long as I can get the sort of performance I do now - perfect 1:1 match from 3750-28500 kc (and 1870-2000 with a loading coil) - I'll be happy.

YTZ - "Frankenbracket" - I like it. http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

Quote[/b] (kl7aj @ Oct. 27 2005,08:34)]Quote[/b] (kd8bsr @ Oct. 26 2005,19:45)]7aj - funny you should mention the Collins mechanical filters. #I have a trio of 'em, just begging for attention. #Hmmm...

I think the next mod will be to the ever-changing Antenna Tuning Contraption Number Three. #I got 'hold of a twin-stator air variable and will put that on the antenna end per a design I found in the ARRL handbook. #It should, in theory, give me more low-end tuning range, as well as eliminating the high-pass characteristic at high impedance. #I'm not sure I like the higher Q that'll result though. #I suppose I can put in another switch, to take out the C-to-ground leg when I don't need it and thus restore the present characteristics.

A long-range project is a sequenced T/R switch for the Apache and R392. #All I need is to find a few good, heavy relays and I'm set.
I still think a reversible low-pass L network is the best antenna tuning contraption. #Conjugate match theory tells us that you match ANY impedance to ANY other impedance with no more than two components. #You might need a real BIG component under some circumstances, but it always works. # I can't for the life of me understand why so many manufacturers crank out tuners with a HIGH PASS t-network. #I always thought a tuner was supposed to SUPPRESS harmonics. #I'm appalled.
http://www.qrz.com/iB_html/non-cgi/emoticons/sad.gif

o well


eric
the way it was explained to me is that the tuner does not tune...
it cancells reactance.
just what i was told by a VERY reliable source. http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

actually as far as what i am building,well:
I have noticed a pattern in wm behavior...
my desk would get excessively cluttered over a short period of time.I decided that if my desk was smaller I would not have that problem.WRONG!
I took the upper shelves off the desk(with a jigsaw)
and made more room on the surface.now i had a pile of shelves in the middle of the floor.
after 2 days of tripping over them I decided to do something with them...
you guessed it.I built a small bookshelf tybe contraption and lo and behold the stupid thing ended up
BACK ON MY DESK!!!
actually takes up less space but it works for me.
as far as electronical stuff...no nothing lately.
my last endeavor ended in sucess and I decided to quit while I was ahead.for now anyways.that might change tomorrow.
never know.

[K9STH]

ZDY:

I believe that Surplus Sales of Nebraska must have found the "mother lode" of 4D32 tubes. They are (have been for some time) selling them for $20 each or $18 each when purchased in groups of 3. Other Internet tube sellers have them from $40 to $50 each.

One of the tube sellers is selling tubes in the old "world" type of RCA box for $99 each. I guess that increases the value of some of my NOS tubes since they are in that type of box.

Glen, K9STH

[k6pme]

Quote[/b] (ki4bnc @ Oct. 27 2005,16:58)]my desk would get excessively cluttered over a short period of time.I decided that if my desk was smaller I would not have that problem.WRONG!
I took the upper shelves off the desk(with a jigsaw)
and #made more room on the surface.now i had a pile of shelves in the middle of the floor.
after 2 days of tripping over them I decided to do something with them...
you guessed it.I built a small bookshelf tybe contraption and lo and behold the stupid thing ended up
BACK ON MY DESK!!!
.
I bet if you go to Barnes and Noble or some similar such place that you can find a self-help book for your problem. Or, open the phone book, look up mental health.......

http://www.qrz.com/iB_html/non-cgi/emoticons/laugh.gif http://www.qrz.com/iB_html/non-cgi/emoticons/laugh.gif http://www.qrz.com/iB_html/non-cgi/emoticons/laugh.gif

[k7mh]

Quote[/b] ] Quote (ki4bnc @ Oct. 27 2005,16:58)
my desk would get excessively cluttered over a short period of time.I decided that if my desk was smaller I would not have that problem.WRONG!
I took the upper shelves off the desk(with a jigsaw)
and #made more room on the surface.now i had a pile of shelves in the middle of the floor.
after 2 days of tripping over them I decided to do something with them...
you guessed it.I built a small bookshelf tybe contraption and lo and behold the stupid thing ended up
BACK ON MY DESK!!!


I know what I would do! I would get a jigsaw and cut the shelf off the desk and just stack it up nearby on the floor! Then I would have more desk space!! (The mind says no sweat we know our way around here no problemo!! The toes say NOOOOOOO!!!!!) http://www.qrz.com/iB_html/non-cgi/emoticons/wow.gif

[w8cbc]

Whenever I put up shelves or provide myself with more horizontal space in some other way, it all gets filled up in short order. It's worth the effort mainly for the jumble reduction.

BNC - cancelling reactance was of course the idea behind the ATC-2. Unfortunately, in some situations it wouldn't do much with the overall impedance. Thus, the ATC-3. A proven design, and it works nice, but the high-pass configuration does still bug me on principle, as it does 7aj. Is just a question of having the parts.

I may get on that loop over the weekend and attempt to work some 15/12/10 with it, just to see if what I've read since I put the thing up means anything. I gotta find a way to drop the local noise. The loop may help. I got so spoiled by the almost total absence of RF noise up north. My problem here is the opposite of many - they can hear me better than I can hear them.

[kb2vxa]

Hi guys,

My latest project is a sound card interface for the 706 Mark so I can do the "exotic" modes. Half finished I found a novel use for it, pre-recorded station IDs. My favorite is Microsoft Sam who sounds like the typical repeater voice ID saying "This is KB2VXA Point Pleasant Beach New Jersey" in a somewhat sing-song voice. The responses range from none to "What the inverted L was THAT?" (;->)

Oh, we all know how we hate the CBers' sound effects, lately the Atlantic City NJ Coast Guard sector field office linked system has developed a mean echo. "Ten four good buddy, what is the nature of your distess distress distress distress.......?" http://www.qrz.com/iB_html/non-cgi/emoticons/tounge.gif

[kl7aj]

Quote[/b] (K9STH @ Oct. 27 2005,17:55)]ZDY:

I believe that Surplus Sales of Nebraska must have found the "mother lode" of 4D32 tubes. #They are (have been for some time) selling them for $20 each or $18 each when purchased in groups of 3. #Other Internet tube sellers have them from $40 to $50 each.

One of the tube sellers is selling tubes in the old "world" type of RCA box for $99 each. #I guess that increases the value of some of my NOS tubes since they are in that type of box.

Glen, K9STH
So now I have to start collecting BOXES as well as tubes? OY.....I hardly have enough room for me ol' Heathkits n HaloCrafters. When I look at the old tube boxes I tossed out by the case...so as to save room for the precious little jugs within....I should be rich by now.

Oh well, live and learn


eric http://www.qrz.com/iB_html/non-cgi/emoticons/rock.gif

[w8cbc]

Oh, hell, I have 2A3s in their original RCA boxes. 10s and 53s too. You know what matched NOS 2A3s are going for. The "purist" audio crowd, heh heh. Maybe the next time I get an urge to clean the place out.

[W0LPQ]

2 years ago recapped a TR-4C/RV-4C/AC-4. Now working on SR-150 SN-006. That is .... er ... fun..!

Built a coax relay antenna matrix for the antennas out back. Works just fine on 24V....Collins surplus relays.

Bill, W0LPQ

[w8znx]

Quote[/b] (kd8bsr @ Oct. 28 2005,08:12)]Oh, hell, I have 2A3s in their original RCA boxes. #10s and 53s too. #You know what matched NOS 2A3s are going for. #The "purist" audio crowd, heh heh. #Maybe the next time I get an urge to clean the place out.
heck don't let them go to the audio fools

Antique Wireless boys still use 2A3's and 10's
in old transmitters

lets see now a 10 hartly osc to a 10 buffer/driver stage
ect all on a nice wood base

Bill Orr wrote more than one article back in 70's
in CQ magzine on building pre 1937 transmitters
using 10's and there are tons of plans for 2A3's
in the Frank C Jones hand book

mac dit dit

[w8znx]

remember when Davlin was asking
few hundred dollars for a 4D32 hi hi

now that they are cheep
no longer have a Viking or 32V transmitter

oh well

if have time still want to build more breadboard jobs

have a few qrp style kits havent built yet

need to do restoration job on a
Stancor 10 P, and to fix about half dozen
other radios

also need to build a HV plate supply
for a four by one,
first half to get the T-368 transformer
out of car trunk and in to basement shack
dam thing must weigh 125 lbs

heavy iron keeps geting heavier every year

yours truly Mac

[K9STH]

ZNX:

How about a Hallicrafters HT-20? It uses a 4D32 in the final as well.

Glen, K9STH

[w8znx]

Hello Glen

oh no,
as much as Id love to play with a Halliscratcher HT-20
I do not need any more am/cw heavy iron transmitters

heck geting afraid to try
picking up an Apache or DX-100 transmitter
much less the mod/ps deck of a johnson 500

one of these days im going to get a good
grip on some heavy iron, #grunt
and finaly break something inside me
that won't be easy to fix

yours truly Mac

realy thought the 4D32 was a fb tube

[ve2nsm]

Right now I'm building my fourth 10/11m duplexer.
Honing my skills http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

[KC9ECI]

Sitting here with the 3rd harmonic, watching Spongebob, eating some M&M's and assembling radials for my new 6-BTV antenna.

[w8cbc]

znx - I'm not letting those 10s go, that's for sure. They're globes and I like the idea of running them out in the open just the way you described.

Lessee... 10 osc, 10 buffer, 45 driver, twin 2A3 output.
24A audio amp, twin 27 driver, 53 p-p modulator.

Now to build it.

[WA2ZDY]

Now I wish I had a 32V again.

[K9STH]

ZNX:

The Apache and DX-100 are light weights compared to the Globe Champion 350A and the Hallicrafters HT-20 (I have all 4 of them). Also, since the HT-20 was the first "TVI proof" transmitter that Hallicrafters made it has shield inside of shield. To be able to work on it one has to remove no less than 144 sheetmetal screws! It takes at least 15 minutes just to remove the shields so that it is possible to service the brute!

But, it is a "nice" transmitter. Covers 1.5 MHz through 30 MHz continuously. Very good modulation and nice keying.

Glen, K9STH

[KA4DPO]

I have a brand new Los Gatos 250-TH in the box. Got it at a hamfest in Augusta, GA years ago to build an AM rig. Also have a brand new 4-1000A, don't know what I'll do with either one of them since I don't have a power transformer big enough to do any good.

Mostly I just build QRP rigs now days, like ZNX my back can't take lifting the big iron anymore.

[N3ATS]

Building a variable output voltage regulator for another project...

...A circuit to allow a alpha/numeric pager to operate an external device when paged.

[KF0RT]

Working on a "simple" screwdriver antenna controller here with a 433MHZ (Part 15) RF remote control.

It's taking longer than expected, but I don't anticipate needing it until next fall. 90% done, just need to find the "tuit" for the last 10%.

73, Rob

[w5alt]

Quote[/b] (KF0RT @ Oct. 28 2005,23:03)]... 90% done, just need to find the "tuit" for the last 10%.
My problem is that I keep finding square "tuits" instead of round ones ...

[KF0RT]

Quote[/b] (w5alt @ Oct. 28 2005,21:13)]Quote[/b] (KF0RT @ Oct. 28 2005,23:03)]... 90% done, just need to find the "tuit" for the last 10%.
My problem is that I keep finding square "tuits" instead of round ones ...
No joke, Walt. Too many projects, too little time (and too much time on QRZ). Big project here is moving a ton of dirt for a retaining wall -- got brick, still digging. I should be working on that right now, but it's dark out. And it's supposed to snow this weekend.

Can I send a little of that white stuff your way? http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

73, Rob

[w5alt]

Quote[/b] (KF0RT @ Oct. 28 2005,23:24)]Can I send a little of that white stuff your way? # http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif #http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif
Sure thing! This week it's been raining on and off (unusual), so the temperature hasn't gotten much above 90 F or so. It'll be another couple months before it gets down to 70 F at night, though.

BTW, I just ordered a couple more digital kits and should pick them up when I'm back in the US for Christmas. I admit - I'm a sucker for most anthing RF and computerized. Should keep me busy for a while modifying and playing. And who knows, maybe I'll even make something useful. http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif

73,
Walt, W5ALT

[w8cbc]

K9STH - the Apache is plenty heavy enough! My back is already shot. Getting that thing up three flights of stairs wasn't pleasant.

I stuck the twin-stator cap in the ATC-3 tonight as planned. Q went way up. I couldn't run full power on 80 or 160 for all the arcing. I also managed to roast a 5k-ohm path to ground in the bypass switch whilst testing the thing, which made tuning up 160 altogether impossible. So I have to admit defeat on this one. I changed everything back to the way it was and flopped the switch around (I don't have another 250V DPDT to hand right now) so the ground leak is on the bypass end.

I also had to glue my ashtray back together. I threw it at the cat for getting into my business after being warned off several times. I missed the cat.

I learned a few things in the negative sense. Otherwise, a wasted night.

I'm just cooking dinner now, 0207 local time.

[WA2ZDY]

I never had a Champion, King or HT20 but I sure remember my Apaches, DX100 and 32V. The 32V seemed the heaviest. It was surely the most solidly built of the bunch. That and I was 13, so maybe I just hadn't built up my boatanchor muscles enough.

$20 for a 4D32. Wow. Makes having a 32V affordable these days. Considering that the rigs themselves now sell for their weight in gold . . .

[w8znx]

hello Glen

heck you are not to pick up a globe chimp
never tryed to pick up
globe king 400, collins 30 K5, or johnson desk
never try to move them all in one piece
globe king break down in to decks
the 30 k and desk pull all the iron out
they get easier to move

last week two of us moved
a big RCA Radiomarine transmitter
but it had no modulatior or power supply

have a big hand truck
but dsnt help geting a Apache on to the desk
or workbench
now if i could get some kid to pull
the t368 transformer out of my trunk

there was a big Collins WW II USN transmitter
basement shack in Chicago
the house had an adition put on it
could not get the radio out of the house
when it came time to tear down the house
3 ops took a chain saw to the house

to be able to get the rig out of the basement
yes it was rebuilt and looks great and sounds great


there is a johnson desk for sale on epay
breaks my heart,
I have sat at that desk
when there was a HRO 60, ranger,and ht 37 on top of it
with globe king 500 to the left

the room this radio is in
once was full of radio gear
its the now all but empty shack of w8cdm sk
Paul and I were going to be old coot ops

yours truly Mac

[K9STH]

The Globe Champion series is in a desk top cabinet. My 350A weighs about 140 pounds which is where the Hallicrafters HT-20 comes in. The Collins 32V series is pretty close in weight as well.

I don't like to carry my HT-20 or 350A very far. However, I can get them from the floor to the desk or workbench. My heavy duty "hand truck" (called a "two wheeler" in this part of the country) is really "handy" when I have to move one of the heavy transmitters from one room to another.

Glen, K9STH

[KC9ECI]

Quote[/b] (K9STH @ Oct. 29 2005,16:05)]#My heavy duty "hand truck" (called a "two wheeler" in this part of the country) is really "handy" when I have to move one of the heavy transmitters from one room to another.
We have several in the shop that we use for moving rolls of laminate amongst other things. We call them "two wheeler" up here too. We had one with inflated tires at one time. The tires eventually went flat, and in the process of trying to get someone to have that fixed, I got tired of waiting and had a couple 'wheels' cut out of wood on the Biesse, mounted them in place of the rubber tires and lettered "Flintstone Flyer" on them. I figured that might embarass someone into doing the maintainence. That was a year ago. I used the Flintstone Flyer to move some laminate Friday...the wood wheels are still going strong.

[WA2ZDY]

Quote[/b] (KC9ECI @ Oct. 29 2005,18:50)]I figured that might embarass someone into doing the maintainence. #That was a year ago. #I used the Flintstone Flyer to move some laminate Friday...the wood wheels are still going strong.
No, someone in your organisation has some sense. Why waste the money on the "repairs" when the fix you engineered is working just fine? If it's been over a year, your idea and work is obviously effective and in no need of further attention.

[kb3mng]

Quote[/b] (N3ATS @ Oct. 28 2005,16:55)]...A circuit to allow a alpha/numeric pager to operate an external device when paged.
I always thought that would be an interesting idea for long distance remote control, but I never had anything to control that I thought was worth the pager service fee.

Are you going to try to decode the message to the pager so you can give the device multiple commands, or will it just respond to the presence of a message?

[w8cbc]

Oooh, that suggests to me digging up a surplus Burk control point unit and wiring all my gumph to it. That T/R sequencer I've been going on about would be a good candidate for channel 1.

I got a new bypass switch for the ATC-3 and wired it in. All is well again. I'll leave it as is now. The ATC-4 will be a low-pass T.

[WA9SVD]

I forgot to mention the small thermonuclear (thermonucular to some) device. Unfortunately, Rat Shack was out of the detonators, with no expected delivery date, and Home Depot was back ordered on the Plutonium.
There's this gopher tearing up my dad's back yard, and 20M RF doesn't seem to bother him...

[w8cbc]

The WLW site has gophers. Lots of them. And the CE ain't allowed by the City of Mason to shoot them. I suggested running the exhaust system of the generator into a set of radial tunnels in the ground. Was told I'm evil. Heehee.