Lmst

From the picture i've ssen before (and from the Yaesu Manual) the #FTX1F was looking a bit smaler than the #IC705. But it looks like the dimensions in the Yaesu datasheet are without the battery. So basicly both radios are quite equal in size (esp. depth).

Future HF Portable Fun Project (Step 1): Fasten HF antenna base to Rush 24 backpack using Diamond HRKS UHF mount and Comet AD-35M UHF to 3/8-24 adapter. Used 2 thin-ties (0.5 x 8 inches) to attach mount. Still need to route coax and add a detachable dangle counterpoise wire. Planning fixed site setup, 20-6 meters (single band at a time) coverage with CHA SS-17 telescoping whip. Also supports VHF/UHF on-the-go with Diamond NR-770 UHF antenna. Outside setup tests next… #HamRadio #IC705

Photo of Diamond HRKS antenna mount with a few of the thin-strip mounting straps.

HRKS mount attached to pack's mollie straps.

Diamond HRKS with UHF mount and Comet AD-35M UHF to 3/8-24 adapter. This is pretty wobbly just sitting on the desk...

Mount with Chameleon SS-17 attached and whip routed through mollie straps up to top of pack. Much sturdier now!

I recently measured #IC705 transmit power 🧵. But I did not dive into output power's dependency on supply voltage. Jürgen DF3PM kindly made me aware of results by George, M1GEO. George found out that (unsurprisingly), output power drops as supply voltage is decreased from 13 V to 12 V or less.

Interestingly and somewhat surprising, output power is stable as supply voltage is increased to 14, 15, or 16 V, though efficiency drops.
https://www.george-smart.co.uk/2024/07/measuring-the-icom-ic-705-rf-power-vs-dc-input-voltage/

Thanks, Jürgen and George!

What is the #IC705's transmit power?

I recently did a bunch of measurements.

Takeaways:

With the power knob at 0%, output can still be as much as 100 mW.

When using the "max power" setting, actual power delivered is always a little lower.

Output power mildly dependent on which band you transmit.

To achieve 5 W output, I'll set "max power" to 10 W and the percentage to 61%.

More details: https://dj3ei.famsik.de/blog/posts/2025/ic-705_pwr/

#Sonate-2 satellite images received on #sstv .
Quite good reception despite only 500mW satellite transmitter.
#rig: #ic705 , 5-el yagi
Tracking and doppler correction with #look4sat.
Transmision schedule: https://www.informatik.uni-wuerzburg.de/raumfahrttechnik/projekte/aktive/sonate-2/information-fuer-funkamateure/
#sat

🇬🇧 Receiving sstv from Fram2 space mission (EN subtitles) 🇵🇱 Odbiór sstv z misji kosmicznej Fram2

https://video.citizen4.eu/videos/watch/b1c56fa9-32ea-439c-aa9b-ddbdd7242cc9

Successful reception of #sstv from #fram2 mission this morning :-). As requested, I am not showing the received pictures before the #fram2ham contest is over: https://fram2ham.com .
#ic705 #look4sat

ic705 receives #sstv transmission from #fram2 mission. Next to it, on the phone, the #look4sat app for satellite tracking.

ISS 2m/70cm transponder reception test with simple vertical antenna

https://video.citizen4.eu/videos/watch/758e370d-fd7f-4eae-873f-817f3d3614e1

Braved the storm this afternoon to do some 24GHz (12.5mm wavelength) #MicrowaveRadio #AmateurRadio.

One contact made with Pete G1DFL over a 24KM path on #SSB and #DStar. 59+20dB both ways.

#Icom #IC705 IF and #Wavelab based transverter & 1.5w PA into a 30cm Andrew dish.

1.5w x 34.4dBi = 4131w ERP!

#uWave #HamRadio #HamR #AmateurFunk #アマチュア無線 #AmachuaMusen

Me, wet and cold, wearing a hi-vis 3M Peltor WS XPI rugged Bluetooth headset with furry boom mic. I’m on top of a hill, in a storm. Behind me is a farm gate, and my 24GHz dish on a tripod.

Rain has stopped for a while, so put a wire antenna up and having a listen around the bands… #HamRadio #HamR #AmateurRadio #AmateurFunk #Icom #IC705 #QRP #AH705 #Shortwave #VanLife #RVLife #Camping

A photo of an Icom IC-705 low power shortwave transceiver on a camping table

I think it was more effort to get the image on the radio than it was designing the QSL card! #ic705

An Icom IC-705 radio in an ARK cage with a custom startup screen.

For #hamRadio fans of #js8, it is #js8QsoParty time again!

https://js8call.groups.io/g/main/viewevent?repeatid=12902&eventid=1597224&calstart=2024-06-08

Problem encountered: After finally upgrading from Debian Bullseye to Debian Bookworm, the old #IC705 sound card string I had used became unreliable; I had to switch.

Highlight thus far was reading a message that some nice person in Florida, USA left for me on their system some time last November. This felt a bit like finding a message in a bottle on a beach specifically written for me!

More fun later today! 😄

I grabbed one of these for my #ic705 from Amazon in the UK. Thanks @oh8hub for the tip!
https://mastodon.radio/@oh8hub/111620156368683104

A hard case, purchased from Amazon in the UK.

An Icom IC-705 in an ARK cage in a case.

An Icom IC-705 in an ARK cage sitting on a desk.

It happened to me with my #IC705, after some digimode stuff on shortwave, that I switched to 2m for our weekly local friendly FM ragchew session - and there was complaint about my carrier with no modulation when I tried to transmit. Turned out the rig still expected "data", not analog input from the microphone.

You are being bitten by this if the mode displays FM-D, or some other XXX-D. If so, touch that mode long, and then hit "data" to toggle it away.

@kr1st @KC8JC @vk2di

Several times now, my #IC705 has refused to modulate using the microphone. PTT works but no audio. Tried different mic, same thing. However, I can work SSB just fine using SDR-Control with the audio coming from my iPhone. Comes good after a while for no apparent reason. Wonder if anyone else has seen this?

Decided to build a Memory Keyer Keypad for the ICOM 705. Printed on Textured PEI Plate on the Bamboo X1C - bottom half printing now. ASA used.

https://ve3ips.wordpress.com/2020/10/22/icom-705-transmit-memory-keypad-box/

#ICOM #IC705

Start of the build a Memory Keyer Keypad for the ICOM 705.

Underside of button board. All keyed to line up for easy soldering.

Some years ago, I was p*sed off when ICOM did a big advertising campaign for the #IC705 at a time when that rig could not yet be bought. They simply hadn't put it on the market yet. But there was no mention of that fact in the ads. A "preorder now!" somewhere in the fine print, or anything of that sort? No.

In the end, I ended up buying it anyway, for it is a good rig for what I want (with a few minor problems). But the advertisement delayed my purchase by several months.

@G0TRT

The #IC705 overheats.

During the eclipse, I continuously sent WSPR (92% duty cycle) on 17m for GSSC. My IC705 overheated at abt 22°C ambient. Max power reduced to 1 W: Still overheating, though much more slowly. Removing the battery pack (which the manual says I shouldn't): Thermal stabilization just short of overheating while the PA long-term generates abt 10 W of heat. I estimate with battery pack, the IC705 PA can take abt 8 W.

One may want to 3d-print a fake battery pack that sports a fan.

IC705 screen capture after many minutes of transmitting WSPR (duty cycle 92%). Picture taken 2024-04-08. Transmit power has been limited to 1W via menu.

The screen shot shows it has been taken on 19:23 UTC. The rig is transmitting at the full 1 W power configured. The ALC is just barely engaging. SWR is displayed at approximately 1.2. The PA drain current is at about 0.9 A. The PA temperature is quite warm, but with a small safety margin to the red area marked "HOT".

The PA drain voltage was about 13 V (from a rechargeable battery). So PA power some 12 W for an efficiency of some 9%.

How long does an #IC705 take to warm up?

Using frequency calibration of WSJT-X on a time signal station at 15 MHz, I took some values this morning.

Initial frequency deviates about 4-5 Hz from that reached after warmup. 1 Hz precision is reached after about 15 minutes; warmup reaches ±0.2Hz noise floor after maybe 35-40 minutes.

An exponential fit suggest deviation is reduced by half every 6.6 minutes. Close inspection suggests actual warmup is faster during the first 11 minutes or so.

An x/y-plot showing those measurement values for which WSJT-X reported SNR above 25 dB and an exponential least-square fit of these values.

The IC705's frequency started some 4.2 Hz below that reached after warmup; the way WSJT-X measures frequency deviation, this led to a positive deviation in the graph.

An early outlier reaches about 1 Hz higher at some 5.2 Hz above final value. At about 7 minutes, another outlier can be seen of maybe 1.2 Hz; some more, lesser outliers at later times are predominantly towards positive values, suggesting the ionospheric Doppler shift tends to increase received frequency more dramatically, decreases are more moderate. Maybe the ionosphere falls faster than it rises. FWIW, the measurements were done during local morning in Berlin, Germany, starting 7:19:39 UTC.

A least-square fit with an exponential function resulted in an initial deviation of 4.1 Hz and the deviation halves every 6.6 minutes. For the first minute or so, the actual values are maybe 0.1 Hz above the fit curve. Until about 11 minutes, the measurement values tend to be below the fit curve, up to maybe 0.4 Hz at 7 minutes. Until about 30 minutes, measured values are again above the fit curve, maximum deviation about 0.2 Hz at 20 minutes. Starting about 35 minutes, the values seem to be below the fit curve and also its limit. That limit is also the y = 0 line; that's how the graph was drawn.

#IC705 frequency calibration:

"Menu / set / function / REF Adjust". provides an (basically undocumented) % "ref" value for fine-tuning.

With WSJT-X and some short wave time signal stations, frequency deviation can be measured (see alt text). The IC-705 errs by always the same some Hz per MHz ("ppm slope" in wsjtx).

I found: One more % IC-705 "ref" value decreases WSJT-X slope by about 0.084 ppm.

Briefly, I pushed slope to within ±0.01. A bit of FT-8 tx later, it was at 0.2.

#ic705

Client Info