Tag Archives: WD8RIF

Eric’s DIY Cootie: “Levon”

Many thanks to Eric (WD8RIF) who writes:

Well, if K8RAT is going to tout Hermione, I guess I need to tout Levon.

My cootie/sideswiper was inspired by an article (http://sideswipernet.org/articles/w9ok-modernization.php) by W9LA about how hams in the 1930s might have constructed a cootie/sideswiper using a ceramic DPST knife switch. I didn’t have a ceramic DPST knife switch, but I did have a nice Leviton ceramic DPDT knife switch which I used as the basis for my cootie/sideswiper. Instead of using tape for the fingerpieces as described in the article, I used Fender guitar picks.

This cootie is the key I use most often for home-based operations.

While operating in the field, I usually use an inexpensive and lightweight Whiterook MK-33 single-lever paddle as a cootie key.

Levon is a handsome sideswiper, Eric! Thanks for sharing his story and your photo!

Thanks to both of you, I feel inspired to make my own “cootie” this winter. Perhaps I’ll try to find some historic context/inspiration as well!

Any other homebrew sideswipers, straight keys, or paddles you’d like to share? Please contact me and we’ll feature your creations!

I’ve got a very special one that’ll be featured later this week. Stay tuned!

A Photographic Tour of Universal Radio’s New Location

In October, 2017, Universal Radio moved from their large Reynoldsburg, Ohio retail store and warehouse to a smaller retail store and warehouse at 651-B Lakeview Plaza, Worthington, Ohio. This is actually Universal Radio’s fourth location in its 75 year history. In 1942, Universal Service opened on North Third Street in downtown Columbus. In 1977, Universal Radio moved to Aida Drive in Reynoldsbutg. In 1992, Universal Radio moved to Americana Drive in Reynoldsburg. Finally, in 2017, Universal Radio moved to the current location in Worthington.

On Friday, November 17, I had the opportunity to visit the new location of Universal Radio  for the first time and I prepared a photographic tour of the new location.

The new location is smaller than the previous location and instead of consisting of one large showroom space, the new location consists of several smaller rooms. (Indeed, the new layout reminds me the layout of one of my all-time favorite bookstores, the Book Loft in Columbus’s German Village neighborhood, which now has 32 (!) rooms of books. No, Universal Radio’s new store does not have 32 rooms!) As can be seen in the following photographs, these rooms are densely stocked. Universal Radio still offers all the items that were available in the previous store location. Of course, just as at the previous, larger, location, some items aren’t on immediate display but are available upon request.

The new Universal Radio storefront at 651-B Lakeview Plaza Blvd, Worthington, Ohio
The new Universal Radio storefront at 651-B Lakeview Plaza Blvd, Worthington, Ohio. There’s more than ample parking.
The sign and entrance to the new Universal Radio store
The sign and entrance to the new Universal Radio store.
Books, with Barb stocking the shelves with the newest "The Worldwide Listening Guide"
Immediately upon entering the store, one will find hundreds of book titles. Here, Barb is stocking the shelves with the newest, just-released, “The Worldwide Listening Guide”.
Magazines
And, of course, Universal still offers several issues each of the two major American amateur radio magazines.
Antennas, shortwave receivers, HTs, scanners + VHF/UHF mobiles
In the main showroom: antennas, shortwave receivers, HTs, scanners, and VHF/UHF mobile transceivers.
HF transceivers
In the same showroom, the HF transceivers, available to operate.
The Heil microphone display
The Heil microphone and headset display.
Used equipment
The Used equipment display: HF transceivers, shortwave receivers, VHF/UHF transceivers, handhelds, and accessories.
Antennas!
Antennas!
More antennas!
And more antennas!
The warehouse area, with Barb and Cathy
Just as with nearly any other modern retailer, Universal Radio’s bread-and-butter is internet and telephone orders. This is just a small portion of the new warehouse and shipping area, with Barb and Cathy busily filling orders.
The warehouse area
A small portion of the warehouse and shipping area.
The well-equipped service area
Universal Radio still has a nicely-equipped service area.

Just as at the previous Reynoldsburg location (and at the even earlier Aida Drive location), the new Universal Radio store is home to several cats which, sadly, I neglected to photograph.

The new store is staffed by the same friendly and helpful people we’ve come to know from the Americana Drive location. During this visit, I saw and spoke with Josh, Eric, Barb, and Cathy.

National Parks On The Air (NPOTA) activations today

IMG_20160519_105823050_HDR

En route to the 2016 Dayton Hamvention, I’m doing a few National Parks On The Air (NPOTA) activations with my my buddy, Eric (WD8RIF).

Eric is currently the number one activator in the state of Ohio.

NPOTA is a great excuse to get outdoors and play radio.

For me, it’s a great excuse to test the LNR Precision LD-11 and my new QRP Ranger portable power pack.

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I am loving the new QRP Ranger power pack–it is the solution I decided on after publishing this post a few weeks ago. It’s a little pricey, but it’s built like a tank, very lightweight, includes a charge controller made specifically for the LiFePo cells, and made here in the USA. It also had a very readable LED display that my buddy Eric says is, “reminiscent of the displays on the Apollo 11 module.” He’s kind of right!

It’s so nice to have both a volmeter and ammeter on the front panel.

IMG_20160519_111039495

 

We just finished activating the Hopewell Culture National Historical Park (I’m writing this post while Eric drives us to our next activation). I made 12 contacts running SSB at 8 watts. Eric made 16 contacts via CW at 5 watts.

We have planned two more activations this afternoon:

  • Charles Young Buffalo Soldiers National Monument at 16:30 UTC
  • Dayton Aviation Herital National Historical Park at 21:00 UTC

I’ll be calling CQ on 14.290 MHz and 7.290 MHz +/-.

Please hop on the air listen and/or answer my call if you’re a ham!

Of course, tomorrow through Sunday, you can find us at the Dayton Hamvention in booth SA0359 in the Silver Arena.

Hope to see you there!

A KX3 Build

Elecraft KX3
Elecraft KX3 by WD8RIF

I recently built an Elecraft KX3 kit and took photographs of the process as I went along. Your host of QRPer.com, K4SWL, thought others would benefit from seeing how simple the process of building a KX3 really is. My thoughts and the photos of the process can be seen here on my website:

http://home.frognet.net/~mcfadden/wd8rif/kx3.htm

An External Battery for the KX1

NOTE: I am embarrassed to admit that I made a significant error in my original measurement methodology and the numbers originally listed below were inaccurate. I’ve redone all the measurements and the text and tables below reflect the corrected measurements. *

Your host, K4SWL, asked me to share my experiences in trying to find a small, lightweight, battery pack for use with my field-portable QRP station. While I’m looking for a battery pack specifically for my Elecraft KX1, what I’m learning should be useful for users of any low-current QRP transceiver.

original 10-cell battery-holder -- click to enlargeCurrently, I’m experimenting with a pair of ten-cell AA battery-holders, one of unknown provenance (photo) and a new, more rugged one from Batteries America (p/n 10AAT, photo). When filled with ten AA NiMH cells, the resulting battery-packs provide about 14v at full-charge. At the 2012 Flight of the Bumblebees, my KX1 generated an indicated 2.6w on 20m and 4w on 40m while being powered by one of these packs; the nearly four hours of low-stress operating during this event did not discharge this pack of 2,000mAh cells very deeply. The use of two AA dummy-cells will also allow the use of eight lithium primary or alkaline cells in an emergency.

new 10-cell battery-holder -- click to enlargeI became concerned about using this style of spring-contact battery-holder when I found an article (link) by Phil Salas, AD5X, in which he reported that this sort of battery-holder is likely to display significant voltage drop under load.

I tested my original battery-holder with ten 2,000mAh NiMH cells and my KX1 transmitting into a dummy load. In addition to measuring whole-pack voltage-drop, I measured the voltage-drop of each of the individual 2,000mAh cells as I transmitted into the dummy load on 20m.

Original Battery-Holder / 2,000mAh cells
Band ΔVpack ΣΔVindiv.
20m 0.76v 0.52v
30m 0.79v
40m 0.75v
80m 0.70v

The sum of these individual drops was 0.52v, so I’m losing 0.24v in the spring-contacts and/or battery-holder’s “transistor battery” output connector.

After replacing the original nylon connector with a pair of Anderson Powerpoles, I tested the same 2,000mAh NiMH cells in the new, more rugged battery-holder, this time only on 20m:

New Battery-Holder / 2,000mAh cells
Band ΔVpack ΣΔVindiv.
20m 0.73v 0.53v

I’m losing about 0.20v in the battery-holder’s spring-terminals, slightly less than with the older battery-holder.

The 0.20v ~ 0.24v drop from the spring-terminals doesn’t seem excessive to me and the difference in these measurements between the two battery-holders is probably not significant. I am more concerned by the 0.53v ~ 0.54v voltage-drop I measured in the individual cells. It is likely that these older 2,000mAh cells, which have been cycled many times, are exhibiting greater voltage-drop than new cells would. To test this theory, I purchased new 2,100mAh cells to measure.

I measured the new cells as above, again on 20m into a dummy load, and found that with each of the battery-holders, the sum of the individual cell voltage-drops was 0.22v, so my speculation appears to have been correct–the new cells do have lower voltage drop under load than the old cells do.

Orignal Battery-Holder, 2,100mAh cells
Band ΔVpack ΣΔVindiv.
20m 0.48v 0.22v
New Battery-Holder, 2,100mAh cells
Band ΔVpack ΣΔVindiv.
20m 0.47v 0.22v

The new 2,100mAh NiMH cells are marketed by Polaroid and cost $6 per four-pack at Big Lots; the least expensive AA NiMH cells available at Batteries America, 2,500mAh Sanyo cells, cost $3 each at the time of this experiment. I don’t know if the Polaroid cells will last for as many cycles as the probably-higher-quality Sanyo cells would but trying the significantly less expensive Polaroid cells seemed like a a good gamble.

As indicated above, the new battery-holder (Battery American p/n 10AAT) is more rugged than my original battery-holder; it holds the AA cells more securely and and doesn’t use a “transistor battery” connector to connect to the load. I replaced the original nylon connector with a pair of Anderson Powerpoles. This battery-holder will be my preferred battery-holder for field operations with the KX1.

In his article (link), Phil Salas, AD5X, recommends foregoing battery-holders in favor of soldered/welded battery packs but I will continue to experiment with battery-holders. I prefer to charge my NiMH cells individually, using an intelligent MAHA charger, rather than charging an entire pack. In addition, my KX1 draws significantly less current on transmit than Phil’s IC-703 does so the the IxR losses I’ll experience will be less significant than that which Phil experienced.

Visit my website to learn more about my QRP operations or to learn more about my KX1 Mini Travel Kit.

* What had I done wrong? I discovered when testing my new battery-holder that the previous measurements of the old and new NiMH cells in the original battery-holder had been made with the KX1 transmitting into a 50Ω dummy load with the KX1 autotuner configured in tune mode instead of in bypass mode; because the KXAT1 autotuner doesn’t sense a mismatch and automatically tune, this meant that transmitter current–and the measured IxR voltage losses–might be also be significantly different than with the KX1 transmitting into a matched load. Comparisons of my original numbers to measurements made later of the new battery-holder wouldn’t be meaningful, so I had to do all the measurements again.