The Icom IC 705:
23/9/2020 It’s arrived in the UK and USA
What do you get with it?
It comes with fused DC lead, Mini Mic (it’s not an option like Elecraft), BP272 battery pack. The DC plug is a little odd, I have several 5.5mm/2.5mm dc plugs but they do not fit most of the QRP radios I have, however, after extensive searching I have found some that do fit and have made up some fused leads for the 705 and other QRP units.
It does not have a tuner/matcher, but why use one? use a resonant antenna, a single or multi band unit, low cost and superb for /P use. If you really do need a tuner/matcher then here is a good one but hunt around for a good price $150? this one cost me £120.00 that’s half the price of the Elecraft one, the mAT-10 30 watt tuner with internal power and charger that lasts for weeks.
The mAT-10 auto tuner 1.8 > 50MHz, supplied with FT817/818 control lead but fully automatic with any transceiver, just push the button!
Base Charger and spare battery packs
There’s plenty of base chargers and spare battery packs available at really good prices, the base chargers (BC-202 genuine Icom made in Japan) are about £20 ($25) and I picked up 4 spare new battery packs for about the same price. The chargers and battery packs are used on many other Icom products. You get about 3 hours of use from the supplied pack (TX/RX). A Chinese copy of the heavy duty lithium pack BP-307 (3300ma) is now available at around £35 ($40)
Antennas (LOW COST & LOTS OF IDEAS)
There’s lots to choose from, a mobile single bander on a small tripod with a radial, a multi-band tapped mobile vertical on a tripod with a multi radial system, a resonant end fed (below) using a 49/1 matching unit would give you multi-bands from one piece of wire and NO TUNER OR COUNTERPOISE NEEDED, COST? around £20.00 > £30.00 plus the wire.
A perfectly resonant end fed using a 49/1 matching unit would give you multi-bands from one piece of wire and NO TUNER NEEDED, COST? £20.00 to £30.00, just add a half wavelength of wire for any single frequency or 20.5 mtrs for 7/14/21/28 as per sweep above & below, so why would you want to pay £80 to £150 for a Ham shop sold version unit? when you can make it yourself.
ABOVE: 7MHz: 1.2/1: 14.1MHz 1.22/1: 21.1MHz 1.22/1: 28.5MHz 1.3/1 with great bandwidth on each band and LOW COST!
ABOVE: Using some of the techniques that are used in our commercial matching units a custom made antenna can be produced offering even more amateur bands. 3.5/7/14/18/21/28MHz @ 1.5/1 vswr
BELOW: Lots of matching transformers and chokes. Buy one get one free!
You could make your own /P kit at a very low cost. A Quality 49/1 (from RFCOMMS) plus make a throwing line/weight/spool, 20.5 mtrs of kevlar line/spool plus 20 mtrs of PTFE RG316 coax all in a nice Cameo zipped case and off you go.
An Ultra Lightweight & Low Cost 49/1 5 Band Resonant Version.
The antenna is resonant on 80/40/20/15/10 and has 1 inductor in the kevlar line rated at 50w pep. The length is around 22.5 mtrs. A shorter 3 band version (40/20/10) is currently in use using a 34 micro henry coil in the line and is 12 mtrs in length.
Above: The 34 micro-henry miniature coils for the 12 mtr long 7/14/28MHz. Just 60mm (2 1/2″) long and fully weatherproofed.
The 110 micro henry miniature coil 130mm long (5″) offering resonance on 3.5/7/14/21/28MHz @ 22.5 mtrs long.
Check out other options/ideas HERE
RFCOMMS matching units, Low cost, Top quality resin potted, optimised dual cores, PTFE wire wound, PTFE SO239 socket, stainless steel strain reliefs. Remember that IP rated boxes are not waterproof if they are not UV protected, this is a common misconception, as when the Sun penetrates the box it will crack it and then the water ingress happens rendering the unit useless.
A smart bracket for £22 > £25 ($30) that fits on to the radio and will then accept a tapped multiband HF antenna and radial or ground plus you can add a diplexer to the bracket so you don’t have to change antenna connections over, a neat idea!
Bracket fits to grounding bolt on IC 705
Low cost stand options below for many QRP radios including the Icom 705
You can pick these up for £15 > £20 or make one in an hour or so, 2 end pieces and some M5 studing with nuts/washers
External Lithium Polymer Packs
Ultra lightweight, handheld, high current, Li-Po 12 volt units available in 8,10 and 22 amp packs that you can carry with ease and can be solar charged or 12 volt dc charged as they have the charging/protection circuits built in. These units are just superb and are used on many African commercial portable radio systems that I have been involved in. Ideal for lots of portable applications including lighting etc. UN Certification and can be transported in aircraft.
There are several nice protective cases around on eBay for the IC-705, the one below has enough room for the Radio, Mic and spare batteries etc, cost around £8. ($10 > 12)
Tests will be carried out using the Icom IC 705 and other low power transceivers to see how the new unit compares, the fun begins!
23/9/2020: Just been montoring 7MHz @ 16.30z – 17.00z, YC9 (Bali) was S8 on IC705 and S8 on FT817ND but the difference was astonishing in the S/N ratio, IC7300 same as IC 705: Antenna used 49/1 with 20.5 mtrs wire, this will always be the test antenna with all the QRP radios for comparison tests.
IC-705 with portable antennas, this mobile unit has a “sliding” coil and there are 2 versions, 80 > 10 and 40 > 10 Mtrs, push it up and push it down for resonance.
QSO’s IN RED:
1/10/2020: Nice qso with HB9CVQ on 7MHz, 5 watts to the antenna above
Early October has seen some good openings even on 28/50MHz. Many stations have been worked in Europe both on CW and SSB including EA9/CN/IT9/5B4/C31/EA/CT/F/DL/PA/EI/GM etc. Good fun with just 10w
8/10/20: 7MHz DF2VP good ssb contact 5w
Audio Tip: I like the speaker on the main unit but as soon as you plug in the speaker/mic the internal speaker is disabled, don’t plug in the 3.5mm jack from the Mic, you then have PTT tx and tx audio via the 2.5mm plug but the receive audio comes out of the main speaker! nice! I would have thought that the 3.5mm plug would carry AF out (Mic speaker) and AF in (Mic), but unplug it and see what happens, cannot find any mention of it in the manuals. Interestingly the 3.5mm plug has 3 poles but it seems it only controls the internal speaker as all the functions on the MIC (buttons up/down and “A” + “B”) still work when it is unpluged.
17/18th Oct: Lots of Eu contest stations worked on the IC 705 and the 49/1, SSB with 5 watts, also switched to IC 7300 and no difference on RX.
22/10/20 VK6 Hrd on 28MHz, also lots of action from Eu on FT8. 21MHz UA3EDQ QSO 57 5 watts. 21MHz 1300z open to Eu/ZS/5B4/SV/UR5/CR2………28.380MHz 13.24 FR4QT S8
So far the IC 705 shines, comparing it with: X5105, FT817 (later version) and the G90 there is NO doubt the receiver is very good and S/N ratio is far superior. I made a recording of FR4QT (Reunion Island) yesterday on 28MHz and when comparing the signal he was S8 on the 705 and audable with dificulty on the 817 & G90
23/10/20: 10.20z ZS6WAB/B 28.204.5 audable on 705 but not on G90/X5105. 10.40z. ES on 28MHz to EA4EUI/EA5 & CT. 28.380 11.00z: FR4QT/S5
24/10/20: LN8W/SE0X/OZ4NA/OV5TV/SM6W + lots more in Eu on 28MHz: IC 705 5W: ZW0 + PY stns consistantly better s/n on 705 compared with other QRP receivers.
30/10/20: ES all PM on 28MHz, IS0BSR in for hours
Cycle 25 on the go, Mega sunspot activity in the past week includes sunspots 6 to 8 times the size of the Earth, super openings on 18 to 28MHz, FR4QT is appearing in Eu nearly every day along with ZS6 beacons and stations, great TEP conditions. Checkout: https://www.spaceweather.com/
So far wkd North America (160Mtrs), South America, Africa and lots in Eu using just 10 watts and a 49/1 multiband unit, very impressed.
There multiplying, now have 2 of them!
Been doing lots of tests between the 705 and: FT817ND/x5105/G90/FRG100/IC703/FX1A/FX1B and decided that they can all go as the Icom IC 705 beats the lot hands down. It is not just a QRP radio it is also a fantastic tool for finding noise problems in the 0 > 200 MHz range, I wish I could replace my car radio with one but it won’t fit in the hole!
13/11: Great opening on 28MHz, 7Q7RU in 599 at times. ZS6 beacons hrd
16/11: 11.20z TZ1CE 599 28.006MHz: also copied on no tuner 1 mtr loop 559, ES?
17/11: VO1FOG S6 SSB 28.480MHz + ES in Eu: DL/S57/I/LA4………..1200 > 1500 Good ES, OE2MBN up to S9 QSO:
20/11: 13.30z 9J2RD SSB 55 TEP
26/11: 10.30z EA8NF “ES” also 5B4: EA8DHV 559: S01WS 55 “ES” Western Sahara: 11.00z FY5KE 529/559 “ES + TEP” in for 40 mins: The Radio Sun 10.7 cm flux: 104 sfu. Mega sunspot activity: More good 28MHz openings possible in next few days but I will be busy installing new GEOCHRON system
27/11: SFI: 106: 9.00z 28MHz 4X1TI/S9+: 1200z: 28MHz CU3AN S9+: FY5KE 559
28/11: 12.30z 7Q7RU/28.500MHz S6: CU3EQ/S9 28MHz: 12.40z 28.500 7Q7RU 59: