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:
The North GA QRP Club gang have added a new annual field event to the amateur radio contest calendar–a field event with an unusual twist. The Peanut Power Sprint is this Sunday, September 29, 2013, from 2000Z to 2200Z.
What’s unusual about this event is that it is open to those operators running QRP, those running more than QRP power, those operating at home, and those operating in the field. Participants will be competing against only those who are in the same class. In addition, both CW and SSB operation are allowed and encouraged.
Here are the full rules, in PDF format: http://www.nogaqrp.org/Peanut%20Power%20QRP%20Sprint.pdf
A couple of items to note in the rules:
Personally, I’m looking forward to be operating as Peanut Power #105, “Salted” (5w, portable).
73, WD8RIF
When the band is open, 10 meters is the band for QRP DXing–great DX can be worked with very low power and very modest antennas.
The entire world congregates on 10 meters on the second full weekend of December for the ARRL 10 Meter Contest. This year this contest falls on the weekend of December 8-9, 2012. Complete rules can be found here: www.arrl.org/10-meter. It is worthwhile to note that this contest allows participation by both CW and phone operators.
We are approaching the peak of sunspot cycle 24 and conditions on 10 meters should be excellent for working DX. Even those not interested in the contest per se should take advantage of the propagation and the sheer numbers of DX stations on the band to work some “new ones”.
I was able to spend about three hours participating in the ARRL 160 Meter Contest this past weekend. I operated CW-only, using my Elecraft K2 running 5-watts, and my primary antenna was my low 195′ Inverted-L tuned with an LDG Z-11 QRP autotuner.
I concentrated on working new sections but even so managed to make 72 QSOs with stations in 30 sections; this translated into an hourly rate of about 24 QSOs per hour–not bad for QRP into a compromise antenna. I worked stations in the states shown in the map below, plus Ontario. (My station is located in southeastern Ohio.)
Although my primary antenna was my Inverted-L, I also shorted the feedline of my windowline-fed 135′ doublet at the tuner and fed the antenna against ground; this antenna allowed me to make one QSO I couldn’t make with the Inverted-L.
I had been hoping to work a DX station or two and heard but wasn’t able to work just one non-US, non-Canadian station, a station in the Bahamas.
Winter is the time to operate on 160-meters. Within the next six weeks we find not one, not two, but three 160-meter contests.
November 29, 2012 (0000-0600 UTC ): QRP ARCI Top Band Sprint (rules) — note that this the evening of Wednesday, November 28 in North America!
November 30 – December 2, 2012 (2200 UTC Friday – 1600 UTC Sunday): ARRL 160 Meter Contest (rules); this contest includes a QRP class.
December 29 – 30 (1500 UTC Saturday – 1500 UTC Sunday): Stew Perry Top Band Distance Challenge (rules); this contest includes a QRP class.
If you don’t have a dedicated 160-meter antenna but have a 40m or 80m dipole/doublet, try shorting the feedline at the radio and work it against ground through an antenna tuner; this will convert your dipole/doublet into a vertical with a really big “top hat”.
This coming weekend is the 2012 QRP ARCI Fall QSO Party, one of the most popular contests of the QRP calendar. This year, new entry categories are based on the antenna used; those participating with a simple wire antenna or a vertical won’t be competing against those using beams or other multi-element antennas.
The Fall QSO Party runs from 1200UTC on Saturday the 13th through 2400UTC on Sunday the 14th.
Here are the complete rules:
http://www.qrparci.org/content/view/8399/118/
I won’t be competing in the Fall QSO Party to win. Instead, I’ll do as I’ve done several times in the past–I’ll use this event as an opportunity for what might be my last outdoor “field event” of the year. A good friend and I will be spending a few hours at Mt. Gilead State Park in north-central Ohio enjoying what promises to be beautiful fall weather, good friendship, and an opportunity to enjoy CW in the great outdoors.
If you participate in the Fall QSO Party, you are very likely to hear stations participating in the Pennsylvania and Arizona QSO Parties. Here are the rules for these two events:
Pennsylvania QSO Party:
http://www.nittany-arc.net/pqppdf/paqsorules12.pdf
Arizona QSO Party:
http://www.azqsoparty.org/rules.html
This coming Saturday, the 15th, is the third Saturday of September and that means it’s time for the New England QRP Club’s annual QRP Afield event!
http://newenglandqrp.org/afield
QRP Afield is one of the best QRP field events in the calendar. Hit the great outdoors this Saturday with a QRP station and make some contacts!
I found an almost perfect bag for carrying a small QRP transceiver, simple antenna, and accessories yesterday in our local Aldi grocery store. The bag (photo) is manufactured by “Adventure Essentials”, is described as an insulated lunch bag, is available in several color-schemes, and cost all of $3.99 plus sales tax. I purchased the grey-and-black version, product number 41991. The bag looks to be very rugged, is covered by a two-year warranty, and the tag even includes a toll-free telephone number for customer service.
As can be seen in the photos, the bag is almost ideally sized for carrying any of the current crop of trail-friendly-radios such as the Elecraft KX1 or KX3, the Ten-Tec 40×0 two-band or 4040 four-band rigs, the Youkits HB-1A three-band or HB-1B four-band rigs, or the MFJ 92xx single-band rigs.
If I didn’t already have a Pelican Case for my KX1 Mini Travel Kit, I could probably be very happy carrying the station in this insulated lunch bag!
Standard disclaimer: I have no relationship with Aldi other than being a satisfied customer.
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.
Currently, 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.
I 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.
