Tag Archives: QRP

Kits, News, Product Announcements, QRP Radios

OpenQRP transceiver available in the UK

October 13, 2013 k4swl Leave a comment

The OpenQRP transceiver (Photo: kanga-products.co.uk)

Graham Smith (G3ZOD) writes:

“Kanga Products (UK) provided the first Open QRP 40m transceiver kits at the UK National Hamfest on 27/28th September.
http://www.kanga-products.co.uk/index.php/openqrp-transceiver

The kit is priced at £89 (GBP) and has an LCD display and front panel controls for Tune, RIT, RF Gain, and 6 push buttons. Output is 6 to 8 Watts at 13.5 V. [T]he Open QRP transceiver also includes a separate chip that decodes incoming CW and CW sent via paddles!

The spec. is available here:
http://www.openqrp.org/files/openQRP_SPECS_R02.pdf

The transceiver was designed by Steve Elliott, K1EL, of WinKeyer fame.
(Kits are also expected to be available in the USA at some point from a separate supplier.)

I was fortunate to be able to purchase one of the kits at the Hamfest. Although I haven’t yet had time to put it together, one purchaser already has his transceiver up & running.

This is an exciting product for us in the UK, as normally items like this are imported from the USA, suffering high tax and import charges.

It begs comparison with Ten-Tec’s Model 506 Open Source QRP CW Transceiver, which is more or less the same concept based on Arduino technology (probably the Rebel was inspired by K1EL’s design, which he started in 2009). The Open QRP is single band and a kit, whereas the Rebel has two bands and is ready-built. The Open QRP has an LCD display and 6 push buttons, where as the Rebel has no display and two push buttons.
When UK companies sell USA amateur products such as the Rebel, they quite often adopt a “dollar – UK pound equivalence” pricing, which makes them far more expensive here than they are in the USA (although the UK companies do have to shoulder the import costs). On this basis, if the Rebel is priced at £199 (GBP), it will make the Open QRP kit less than half the price at £89 (GBP).”

Many thanks for the info, Graham! Please let us know about your experience building and getting the OpenQRP transceiver on the air!

News, Portable, Product Announcements, QRP, QRP Radios

LNR Precision introduces the FX-4: a four band CW/SSB transceiver

September 16, 2013 k4swl 1 Comment

I saw a prototype of the FX-4 at the Dayton Hamvention this year. Initial impressions are that it is well-built and easily back-packable.

I will see about reviewing the LNR FX-4 after they become available.

Many thanks to Chris (K4RCH) for the tip!

(Source: LNR Precision)

It is has been a few months since we announced the FX-4 Transceiver but it is getting very close to being available for purchase. For those of you that are friends of our Facebook page or visited our booth at Dayton Hamvention got an early peek at it. Here is an updated picture and it will be a very sharp black color. Other pics are on theFacebook page. We have been making some last minute tweaks that we think you will really like. We plan to offer it for purchase under $500 and you can add your name to the wait list which can be found at the bottom of our purchase page.

FX-4 Specs

Transceiver size in inches	4.10L X 2.8W X 1.5T
Transceiver Weight	12.8 oz.
Current Drain on receive	250-270 ma
Current Drain on transmit	1200 ma
Receive/Transmit Bands	7.000.00 to 7.300.00 MHz 14.000.00 to 14.350.00 MHz 9.999.00 to 10.150.00 MHz 18.068 to 18.168.00 MHz
Frequency control	75 MHz
Display type	LCD-128×64
Transmitter Max output power	5 watts CW 5 Watts SSB
Spurious emissions	-43dB at 5 Watts
Side tone pitch	550Hz to 1500Hz adjustable
Receiver sensitivity	0.3uV
Selectivity	-3dB/ 2.6K -40db/ 4.5K
Audio Output	1 Watt with 8 ohm speaker
Keyer	Iambic A & B adjustable speed from 5 to 40 wpm
Memory Storage	10 per each Band total of 40
DSP filtering	300KHz, 500KHz. 1.3KHz, 1.6KHz, 1.9KHz, 2.2KHz, and 2.5KHz.
VFO Drift	<5Hz after 5 minute warm up at 30c (<10Hz after 30 minute operation @ 40c)

Announcements, Portable, Product Announcements, QRP, QRP Radios

Hamvention: Tokyo Hy-Power’s XT-751 5W HF HT

May 19, 2013 k4swl 10 Comments

I was very surprised to find this handy talkie, the Tokyo Hy-Power XT-751 HF handheld transceiver, at the Dayton Hamvention. This radio will cover from 40 meters to 6 meters in both SSB and CW. It will also have an internal ATU. It is only a concept radio at this point.

Tokyo Hy-Power hopes to have this radio in production mid 2014.

Announcements, Hamvention, Kits, Product Announcements

David Cripe’s NM0S Cyclone 40 Meter Transceiver kit

May 10, 2013 k4swl 3 Comments

Readers, I just received this release:

A new kit from the Four State QRP Group and David Cripe (NM0S)

NM0S's Cylcone 40M QRP transceiver. Look for it at Four Days in May! — NM0S’s Cylcone 40M QRP transceiver. Look for it at Four Days in May!

Arising from Dave’s entry in QRP ARCI’s 72 Part Challenge Design Contest in 2010, the Cyclone 40 is an enhanced version of the original design. The transceiver designed for the design contest had 72 total parts, performed well, and won honorable mention. This improved version has less than 100 components and even better performance! The kit features all through hole parts and easy assembly. The receiver is a superhet design with very good sensitivity and selectivity, and tunes the entire 125 kHZ CW segment of the 40M Band – and does so at a comfortable tuning rate. A frequency readout is included so you know where you are at all times.

This is a complete kit, including the enclosure. A high quality board package includes the pc board, front and back panels, the sides, and top and bottom all of which make up the enclosure. The control and jack labels are silk screened in white letters and vividly contrast with the black solder mask, and the holes for the connectors and controls are pre-drilled. The ends are “dovetailed” together making a very rugged, easy to build, and attractive enclosure.

Features and Specifications

General

Enclosure: A very nice predrilled and silkscreened enclosure is included. It’s easy to assemble and looks great.
Ergonomics: Smooth solid tuning, a quiet receiver with QSK and well behaved AGC. Nicely laid out front and rear panels.
VFO: The VFO is a simple PTO design, is very stable, and also quite easy to build
Sidetone: Included!
AGC: Audio derived, fast and smooth.
Frequency Range: 7.000 – 7.125 typical.
Tuning Speed: 10kHz/knob turn typical.
Stability: 300 HZ the first 5 min after power up, less than 10 HZ/hour after that.
QSK: Fantastic QSK! Full Break in, excellent muting, really fast!
All Through Hole Parts There are NO SMT parts in this kit, and only three easy to wind toroids.
Dimensions: 4.4 x 3.6 x 1.9″
Power Connector: 2.5×5.5mm coaxial, center positive. Should be fused at 1A, fast blow at PS
Antenna connector: BNC

Receiver

Configuration: Superheterodyne, 11 MHZ IF, 4 Crystal IF Filter.
Sensitivity: MDS (Minimum Discernable Signal) -125, Typical, below the normal 40M band noise level.
Selectivity: Four crystal, 500 HZ IF filter
IMD3: 90 dB typical, better than most commercial gear!
IP3: +10 dBm typical – another very good number
Frequency Readout: 3 or 4 digit CW, 1 kHz or 100 Hz resolution (user selectable), developed by Adrian Hill, KCØYOI.
Band Edge Marker: A band edge marker is heard at 7.001 MHZ
Headphone Jack: 1/8″ stereo, standard earbud/Walkman® headphone compatible
DC Current consumption: 30 ma typical at 13.6 VDC.

Transmitter

Configuration: Stable, Wide Range VFO (PTO design), Efficient Class E Final.
Spectral Purity: All harmonics and spurs less than 50dB below the carrier.
Output Power: approximately 4W into 50 ohms
DC Current consumption: 500ma typical at 13.6 VDC Will operate down to 9v DC.
Key Jack: 1/8″ stereo, grounded shell, switching the tip keys TX. Contacts accessible for an internal add-on keyer

Kits should be available at QRP ARCI’s Four Days in May conference at Dayton, and will be for sale on the Four State QRP Group’s web site approximately May 20th. The final price hasn’t been determined yet but should be less than $100 plus shipping.

Conferences, Portable, SOTA

SOTA at the Charlotte Hamfest, Saturday March 9th

February 20, 2013 k4swl 2 Comments

If you’re planning to attend the Charlotte, NC hamfest (March 8th and 9th), make a point to join the SOTA (Summits On The Air) forum. Christian (KF4LXB), provided me with details:

The forum itself is from 11:45am-12:45pm [Saturday March 9th] in the Cabarrus Room B. There will be total of five of us “SOTAteers” KF4LXB, W4ZV, KI4SVM, WH6LE, and W4ZTM with our kits. We hope to be able to set up a table outside of the conference room so we can have some extra “show and tell” time with our rigs for those interested. We want to get the word out to as many people as possible so we can share about something we all love.

Forum page: http://www.w4bfb.org/hamfest2013/forum_sota_webpage.html

Hamfest site: http://www.w4bfb.org/hamfest2013/hamfest.html

SOTA is serious QRP fun. Thanks for sharing this, Christian!

If you have a QRP related event you would like to publicize, simply contact me with the details and I would be happy to post it on QRPer.com.

Funny

Just a reminder…

October 6, 2012 k4swl Leave a comment

News, Portable, QRP, Videos

Video: See a prototype Begali Adventurer in action aboard the USS Slater

September 21, 2012 k4swl 2 Comments

This video features operations of the QRP DE-Xpedition aboard the USS Slater. Among other innovations, they show a protoype Begali Adventurer in action. The Adventurer is a miniature set of paddles which attaches to portable QRP rigs like the new Elecraft KX3.

News, Product Announcements, QRP Radios

Ten-Tec Argonaut VI: On schedule for ordering, shipping later this fall

September 8, 2012 k4swl 3 Comments

I just received word from John Henry at Ten-Tec that their time frame for production runs of the Model 539 (Argonaut VI) is on-track with estimates provided at the 2012 Dayton Hamvention.

John said:

We are running a small production run right now, working out the kinks of getting it into production. Most places call these “Pilot runs”. Pilot Runs basically get the factory up to speed with the units before we go to full scale production quantities.

He doesn’t see any reason, at this point, why they wouldn’t hit the late fall 2012 ship dates. He also said that they’re working hard to possibly take orders for the Argonaut VI at the 2012 Ten-Tec Hamfest being held at their factory in Sevierville, Tennessee, September 28-29th.

According to John, several Ten-Tec customers have said that they are going to buy a Model 539 and the Model 418 (companion 100 watt linear amplifier) when the 539 starts shipping.

I will attend the 2012 Ten-Tec Hamfest and plan to post updates on QRPer.com from there.

Grab And Go, Portable, QRP

An External Battery for the KX1

August 29, 2012 WD8RIF 1 Comment

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	ΔV_pack	ΣΔV_indiv.
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	ΔV_pack	ΣΔV_indiv.
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	ΔV_pack	ΣΔV_indiv.
20m	0.48v	0.22v

New Battery-Holder, 2,100mAh cells
Band	ΔV_pack	ΣΔV_indiv.
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.