ARI Sanremo Home Page Home Page Nominativo di Sezione ARI Sanremo
Home Main Menu Sezione ARI-RE Award Liguria EME Diploma Sanremo Search Members Downloads Forums Guestbook Login

Toggle Content Trova nel sito

Toggle Content .:Translate Language
Please select to change language

Klicken Sie auf Sprache ändern

Sélectionner pour changer la langue

Haga clic para cambiar el idioma
Autori › QRP Accessories
QRP Accessories

QRP Accessories

QRP... the meaning of a great passion

"Some times is not important what we are doing,
but it becomes important how it is done!"

Premise – Useful accessories for QRP... and not

       It is difficult to believe that in such a lucky country as it is Italy, for the climate and for his favourable exposition the sun that is so underutilized as source of energy.
I am using since many years HF-V/UHF stations, up to 100 watts, powered with solar equipments. I switch to the normal electricity net when I use high power and longer transmission time. I think therefore the solar equipments very useful even not needful for portable operation and for QRP activities!

Portable power supply

QRP portable power supply, easy to assembly, to be carried in the bag; built up considering the weight and having various protections against RF, this is a main reason of several problems and breaking. It utilizes every useful safeties to keep the safe side; it is protected from short circuit, adjustable, AC filter. Load about 1,5 A.

Drawing     Picture

Download Portable power supply (drawing and picture)

Base Supply power

This supply power is absolutely sure, it is designed to solve every problems that can happen during the usage, operator distraction too. It is self protected for internal and external damages. It uses a special integrate circuit able to be set for the maximum intervention level chosen by you (beyond it there will be damages to the operator). The precision trimmer is VR3, the IC2 make short TY1 VR1 that will melt F2. You have to remember to regulate the end excursion of VR1 (that has to be putted on the front panel) using VR2 (put inside in parallel). Adjust VR3 some hundred millivolt higher, you will have the maximum possible protection (for the impossible we are not ready). This "equipment" can also be used as battery charger.
If you analyse well the sketch it tells you almost everything.

Drawing     FRont     Internal

Download Base Supply power (drawing and picture)

Antenna tuner (1)

This is a small tuner cm. 8,8 x 5,5 x 6,5, weight only 250 gr. to be used for QRP in Field Day and at home too. It is useful to tune dipole antenna having coaxial cable of 75 or 50 Ohm but also end fed antenna having medium or high impedance, can support higher power than QRP but never saturate the toroid. Be careful during antenna tune opearation. Even if you are QRP use lower power to avoid to destroy your amplifier that almost surely it is not protected from return high current. In this minituner wattmeter is reading relative measure, as it has to read RF going out when changing bands. An indicative gauge could be added.
Number of turns on toroid T1 (diameter 25 mm.) are six on primary and thirty-six on secondary.
Plugs are seven but depending from your needs. EG do you want to tune frequencies in the range 3,5 MHz and 30 MHz or only amateur bands? My intention is to tune every frequencies, I made: total coil from 3,5 to 7 MHz, 9 turns from 7 MHz and up; further 5 turns up to 10 MHz, then 5 more turns below 14 MHz, 4 turns from 14 MHz and up, 3 turns 18/21 MHz, one turns from 24 to 30 MHz. In any case all those plugs must be tested according to your needs.
During tests use a low power TX, 10/15 W and well protected. T2 is a simple separator (diameter 13 mm.) for the wattmeter; it has one turn in the primary and 31 turns in the secondary of a rigid and very thin wire. I have tested it for short time using much higher power, with antenna perfectly resonant but also not, it is wise do not circulate more then 30 W, due to insulating turns and for the saturation of the toroid with relevant losses.

Drawing    Internal drawing    Front    Internal picture   

Download Antenna tuner (drawing and picture)

Antenna tuner 160 m. to 10 m. (2)

This tuner can tune every antenna types... dipoles, inverted vees, random wire, vertical antennas, mobil whips, beams, using coaxial lines, a simple wire or twin lead. 150 Watts is the maximum power as it has been used a toroid for 160 m. Working on higher frequencies the power can be increased. It is small, versatile, made according to old fashion; valid for OM that would like to utilize his hands. Using a coil with a good Q and capacitors well spaced can be reached a good result. It is also valid to receive. From the picture it can be noted that the cover is cut covered with Plexiglas to avoid parasite absorptions. Even better if whole cover is made by non magnetic material.

Drawing     Picture

"Automatic antenna tuner" - Elecraft T1 (3)

From Elecraft is available, in kit, this tuner, it is dedicated to his equipments but this kit is separately powered and equipped with a processor that can be used with almost any RTX; furthermore for the first time is offered, due to assembly difficulties, already mounted. It can be used together with FT-817 (even inside as per Max IK1FVO) being it a spread example of small size radio. This tuner makes the transceiver well protected against RF; it has no consumption, neglettable weight, size similar to a match box but having a high interest.
Main data: it works with 0,5 W, try to tune 1,5:1 or even better, 9 V battery, can support up to 20 W SSB and 10 W in FM and digital modes, range 1,8 to 54 MHz, tune time 1 or 2 seconds, Weight with box and battery 140 gr., sizes 11,2 x 6,3 x 2,3 cm.
Max IK1FVO improved the miniaturization using the kit and put it instead of batteries, changing them in three litio types for mobile telephones 3,7 V 1200 mA in order to use the radio in QRP for a certain period.

Elecraft T1


It is a very useful circuit for every QRP having an analogical VFO. TXO programmable for 25 KHz or for 50 KHz.
Adding a small antenna can be used as reference in a laboratory.


Audio Filter

This filter in low frequency can solve the problems in a simple and easy way when the RX of a QRP or a different RX is not provided with quartz filters.

Audio Filter

Modern Lantern

This lamp is not a needful accessory but in certain circumstances can be useful. You have to imagine to be far from normal energy sources, may be you have your solar panel but it is raining... What remains to get some energy for RTX batteries or light?
You can use your hands! This lamp gives light or recharges some batteries using hands!
You have to turn a lever, a spring is charged that allows to a small dynamo to turn giving energy to a small lamp or recharge two or more NiCD batteries, easy. You have to turn the lever (spring charge) thirty seconds. The charged spring allow the dynamo to turn for two and half minutes. Supplying light or battery recharge. Therefore about twelve minutes of manual recharge can supply one hour light. It seems to be easy... but try to turn the lever for ten, twelve minutes successively... it is almost impossible!
The two internal batteries, now over sized, and the two added give light for six hours; it is necessary to begin having the batteries well charged and according to the time or strength, then partially complete turning the lever.


Solar panel "El... libro"

It is a mini solar panel, size as a book, very light, almost pocket, easy to build. It can obviously supply the transceiver only partially, but in portable conditions can be useful. It can supply about 300 mA if well oriented and in the good period. It is not necessary the regulator due to the limited current; a voltmeter or a amperometer to be used orientate it toward the sun.
Sizes: cm. 21 x 15, weight 350 gr.


Solar panel "Green Power"

I have provided energy from a solar panel for the following radio: HW9, Elecraft K2, FT 817 and FT 897. It happen to me to be in portable situation on the summit of a mountain (see SOTA), for a quite long time; a solar panel is solving most of supply problems. I have chosen for a flexible panel, to trample on, strong, easy to transport and to set everywhere: on the land, hang up to a tree, put above the car. During the night as insulating under the sack.
It has a good efficiency, in average conditions in our part of the world it can supply 23 W, 1,5 A.
Sizes cm. 122 x 34, weight 1300 gr. I have read also 22 V, therefore to recharge batteries or to supply power to a RTX must be used a regulator.


Solar panel "Oh Sole mio! It is now inside my battery..."

In case the sun is the unique source! When you are in an insulated place, when you have to supply an electronic device as a PC, a RTX, when you do not want to make noise but a solar ray is available, this is your solution! A new generation solar panel, a lithio battery of 3 or 4 Ah. This a modern answer to solve every problems in supplying small quantity of electrical power, considering also cost, weight, safety and cleanliness.
Data: Solar panel ( External link ) 12,7 V, 800 mA, (700 mA at average sunstroke);
Size: mm 270 x 300 x 8, weight 750 gr.
Battery: lithio 12,7 V; size: mm 70 x 60 x 40, weight 250 gr.
Therefore all included is less than one Kg.
Orientate the panel towards the sun using a voltmeter for the maximum output and remember to move the solar panel during the day from East to West! If you need more power you can place several solar panels in parallel with a regulator.


Key "Mini Keyer"

You cannot go on the mountains with a very small RTX QRP and a large and heavy paddle; what I am proposing is very little, made completely by hand to have fun with homemade tool. It is made with few essential elements, easy to find and to work. It has a limited weight; you can keep with only two fingers. It works better than some expensive professional devices; I am using it since ten years at home and outside in several contests.

Drawing     Picture

Download Mini Keyer (drawing and picture)

Keyer and Paddle for portable radio

Keyer, as many others electronic equipments, became smaller and lighter...
(See n. 1 on the picture) Microkey vertical
(See n. 2 on the picture) Paddle mechanical
(See n. 3 on the picture) Paddle magnetic
They are so light that it is necessary to keep them fast!


Keyer "Tam tam el key"

It is unique, new, simple. It allow you, for the first time, to experience the emotion to be part of an electronic circuit! Consumption 11 mA, without battery, size similar to a stamp!
You can play CW like music. Be careful if outside is raining, the keyer must be preserved from the water!

Drawing     Picture

Download Tam Tam el Key (drawing and picture)

Regulator for solar panel

For a correct usage of batteries and RTX a regulator cannot be missing (normally they have high costs). This is simple to build up, it is small, light according to portable philosophy.

Drawing e disegno     Picture

Download Regulator for solar panel (drawing e picture) 

Wattmeter, dummy load

When you build an equipment for QRP soon or later you have to check it or to make some measurements. In all these cases the Wattmeter/Dummy Load becomes useful. The photo and the sketch are self explanatory.

Drawing     Picture

QRP: "Q"uelle "R"adio "P"iccole e... il sole (Those small radios and the sun)

It is since the 17th March 2000 that the sun supplies power to my K2. The sun gives power in both situations as base station and when I am walking on the mountains for SOTA.
During last seven years my K2 has been upgraded internally, it has received a Ni-MH battery then a Litio ones but his power supply has been only from the sun.
I have made 38725 QSOs using all modes, taking part to international Contests reaching, some times, also important places. I wrote about my antennas, the effort to maintain those levels but I have said few words about the importance of the sun and my K2. It is now possible to reach in QRP important targets or simply have a QSO with far friends or to follow a DX station. Then the sun, together with a modern equipment like K2, allows you to make direct QSO, without any satellite, using very small bit of RF.
Look on the picture:

  1. Solar panel: size 270 x 300 x 8 mm, 12,8 V 800 mA (average sun), weight 630 gr.
  2. Battery recharge: for litium batteries 3 cells 7,4 V 11,1 V input DC 12-15 V output 750 mA. Weight 44 gr.
  3. Battery: two, in parallel, 3 cells Li-ion/Li-Po 9 Ah; size 145 x 45 x 35 mm, weight 630 gr.
  4. RTX: Elecraft K2 upgraded up to DSP, with internal modifications, litio batteries 4 Ah. Connector for solar panel, internal-external battery. Connector for digital signals, connector for vertical keyer, bnc connector for 160 m. antenna. Filters for digital signals.

Click to enlarge     Click to enlarge

"Ruspante" I1BAY - I QRP Club #309

Italian version

(3614 reads) Printer Friendly Page

[ Return to I1BAY ]

Nominativo di Sezione
Sezione A.R.I. Sanremo - 18.02 codice ASC che per la Sezione è G08

La Sede si trova in corso Mazzini n° 1, a fianco del Campo Sportivo, in Sanremo. La Sezione è aperta tutti i martedì, non festivi, dalle ore 21 alle ore 23 circa.

Indirizzo Postale:


Scrivi al Segretario
Indirizzo di posta elettronica certificata

Webmaster IZ1OQB PINO

Contatto per il Webmaster
Regolamento del Sito | Note Legali/Disclaimer | Come trovarci

Best viewed 1024x768 +

Questo sito appartiene alla Sezione ARI di Sanremo (IM) e non rappresenta una testata giornalistica in quanto viene aggiornato senza alcuna periodicità.
Non può pertanto considerarsi prodotto editoriale ai sensi della legge n. 62 del 07.03.2001.
I loghi, i marchi e gli script usati in questo sito appartengono ai rispettivi proprietari e a CPG-Nuke Team.
Questo sito utilizza la versione 9.2.1 di Dragonfly CPG-Nuke.
Theme by i1yst
Tutti i testi, le foto e i disegni tecnici sono esclusiva proprietà di © 2002-2013
Vietata la riproduzione e la copia, anche parziale, senza la previa autorizzazione di

All content are protected by the copyright law and may not be copied without the express permission and the active reference to a source!
Web stats

Interactive software released under GNU GPL, Code Credits, Privacy Policy

placeholder Support   Dragonfly   XHTML valid!   CSS valid!   Level Double-A Conformance icon, W3C-WAI Web Content Accessibility Guidelines 1.0   RSS valid!   Robots valid!   PHP   PhpMyAdmin   MySql   Get Adobe Reader   Unicode   Add to Google placeholder