Hi Darko,
thanks for your testing. I haven't tried a factory reset yet, but it seems to be a good workaround.
You can see the effect in this video from VK3VRS Richard.
https://www.youtube.com/watch?v=3JcsH6lP448
I guess it just needs to remove a threshold (in the next firmware).
73 de Wilhelm DG2YK
IC-905 - Commercial FM ATV Transceiver
Forum rules
This forum is run by the BATC (British Amateur Television Club), it is service made freely available to all interested parties, please do not abuse this privilege.
Thank you
This forum is run by the BATC (British Amateur Television Club), it is service made freely available to all interested parties, please do not abuse this privilege.
Thank you
-
WiSi-Testpilot
- Posts: 6
- Joined: Sun Nov 24, 2024 10:17 am
-
WiSi-Testpilot
- Posts: 6
- Joined: Sun Nov 24, 2024 10:17 am
Re: IC-905 - Commercial FM ATV Transceiver
Hello.
I have now also performed a full reset on my IC-905. PAL now works!!
However the AV output is still switched off when no signal is received.
So a blue screen is shown, not snow or weak signals.
If a signal arrives, the monitor output is switched on with a long delay of a few seconds.
Sometimes snow/noise appears randomly.
The overall quality is quite good though, see the image.
The components were:
Sony RX0 supplies the HDMI image.
HDMI (1.3) to AV converter, set to PAL.
TX: IC-905, Filter 1, Filter 1, 2 and 3 hardly differ.
==== 1 m AIR ====
RX: IC-905.
AV to HDMI converter.
Ninja Flame Display/Recorder.
VY 73 Wilhelm
I have now also performed a full reset on my IC-905. PAL now works!!
However the AV output is still switched off when no signal is received.
So a blue screen is shown, not snow or weak signals.
If a signal arrives, the monitor output is switched on with a long delay of a few seconds.
Sometimes snow/noise appears randomly.
The overall quality is quite good though, see the image.
The components were:
Sony RX0 supplies the HDMI image.
HDMI (1.3) to AV converter, set to PAL.
TX: IC-905, Filter 1, Filter 1, 2 and 3 hardly differ.
==== 1 m AIR ====
RX: IC-905.
AV to HDMI converter.
Ninja Flame Display/Recorder.
VY 73 Wilhelm
- NJAFLM_MOV_snapshot.jpg (181.54 KiB) Viewed 8577 times
Re: IC-905 - Commercial FM ATV Transceiver
March 26, 2025.
I finally have an IC-905 at my disposal to conduct the long-planned comparison test.
In the following test, we have perfect conditions: both devices are connected via coax ( no external interference )
and signals are attenuated so that the S meter on both devices shows "S8"
( not too weak and not too strong – RF POWER 6% on both devices ). Picture 1
1. Selected bandwidth: 17 MHz ( +-8.5 MHz ) FIL 1 on both devices
2. Test frequency: 1265 MHz ( preamplifier enabled on both devices )
3. Video input set to 50% on both devices ( factory default ) Picture 2
4. Video output set to 50% on both devices ( factory default ) Picture 2
5. Latest 1.15 software version in both devices!!
6. For this test, the video signal comes from a PM5570 video test signal generator ( output 1Vpp ) and is added to the transmitting section of IC-905 Picture 3
7. The received signal is displayed on an EV4161 waveform monitor from Electronic Visuals.
If ICOM has set all parameters correctly, then the result should be 1:1 ! ....correct ?
The quality that goes into the first IC-905 must come out of the second one IC-905 without any loss !
======== Test beginnt - Test begins =========
1. Video composite standard signal applied to the video input of IC905 - looks good in the TX window, saturation is good!
2. PTT button pressed.....
The picture is there, and the color is there too. We'll see what the meter says...
Connected the wave monitor to the video output of my IC-905, pressed PTT - transmitting...
I finally have an IC-905 at my disposal to conduct the long-planned comparison test.
- 1.jpg (932.11 KiB) Viewed 7185 times
and signals are attenuated so that the S meter on both devices shows "S8"
( not too weak and not too strong – RF POWER 6% on both devices ). Picture 1
- 2.jpg (19.56 KiB) Viewed 7185 times
2. Test frequency: 1265 MHz ( preamplifier enabled on both devices )
3. Video input set to 50% on both devices ( factory default ) Picture 2
4. Video output set to 50% on both devices ( factory default ) Picture 2
- 3.jpg (477.98 KiB) Viewed 7185 times
6. For this test, the video signal comes from a PM5570 video test signal generator ( output 1Vpp ) and is added to the transmitting section of IC-905 Picture 3
- 4.jpg (109.67 KiB) Viewed 7185 times
If ICOM has set all parameters correctly, then the result should be 1:1 ! ....correct ?
The quality that goes into the first IC-905 must come out of the second one IC-905 without any loss !
======== Test beginnt - Test begins =========
1. Video composite standard signal applied to the video input of IC905 - looks good in the TX window, saturation is good!
2. PTT button pressed.....
- 5.jpg (149.25 KiB) Viewed 7185 times
Connected the wave monitor to the video output of my IC-905, pressed PTT - transmitting...
Last edited by oe7dbh on Mon Mar 31, 2025 12:50 pm, edited 2 times in total.
Re: IC-905 - Commercial FM ATV Transceiver
- 6.jpg (53.28 KiB) Viewed 7184 times
- 7.jpg (96.82 KiB) Viewed 7184 times
( I'm thinking about the exact same hardware configuration - QSO with two IC-905s and no other manufacturer's products !! )
Here below are the other three received standard signals again...
- 8.jpg (689.4 KiB) Viewed 7184 times
- 9.jpg (597.45 KiB) Viewed 7184 times
- 10.jpg (119.31 KiB) Viewed 7184 times
Re: IC-905 - Commercial FM ATV Transceiver
============= Test 2 beginnt - Test 2 begins ==================
Same order as the first test, here is the result…
Only a slight difference in level, otherwise hardly any change compared to the images above in Test 1.
Under such perfect conditions with two identical devices, the quality should be 1:1 right ?
- 1.jpg (172.89 KiB) Viewed 7179 times
- 2.jpg (100.67 KiB) Viewed 7179 times
- 3.jpg (562.45 KiB) Viewed 7179 times
- 4.jpg (607.01 KiB) Viewed 7179 times
- 5.jpg (595.23 KiB) Viewed 7179 times
Under such perfect conditions with two identical devices, the quality should be 1:1 right ?
Last edited by oe7dbh on Mon Mar 31, 2025 10:22 am, edited 3 times in total.
Re: IC-905 - Commercial FM ATV Transceiver
Defects discovered in both tests:
1. Frequency response in the 2 MHz to 5 MHz range could be linearly boosted from 0 to 1 dB.
2. Audio carrier level is 6 dB too low and should be boosted.
3. ICOM designers chose a poor component for the connectors ( audio-video input and audio-video output ). The 4-pin 3.5 mm ( 1/8 inch ) jack (of which only 3 are actually used) doesn't always make proper contact. Once again, they skimped on connector quality for such a cheap €4,000 device.
This defect was noticed in both devices and both jacks !! - They could have used something different, with more safety, right ?
How does this defect affect operation ? - See here in a short 19-second video...
https://www.youtube.com/watch?v=ZFj600cUrG4
4. The scope of delivery is missing an original ICOM AV cable with the correct 600 ohm and 75 ohm impedance for the output and input jacks, respectively; then perhaps there would have been less of a problem with the contact.
Additional test with smaller bandwidths, 10MHz FIL2 and 5MHz FIL3
Note:
In the FIL3 5MHz BW position, the audio subcarrier can only be used up to 5.5MHz!!!
Higher carrier frequencies ( such as 6.5, 7.02, and 7.20MHz ) do not pass through the filter.
From approximately 3.5MHz onwards, the frequency response is severely cut by the filter, and the color subcarrier only partially passes through. The higher audio carriers are completely eliminated by internal filters and are therefore inaudible.
And below, the distance between the carrier and the audio carrier is also measured, for various signal BWs with the audio carrier set to a fixed 6.5MHz ( Info: with the 17MHz BW FIL1, the audio carrier should be approximately -20dB ).
Same level and carrier spacing values on my IC-905 and the S58RU IC-905 device !!!
Final Word:
A test technician will certainly find many errors in the IC-905's analog signal processing that do not comply with the standard ( some of which can be corrected by software changes – it just requires goodwill on the part of the ICOM technician/programmer ). BUT for most TV amateur radio operators, only a stable color picture is important ( which is also present here ) to conduct QSOs; they don't have the measuring equipment to check the video signal. If that was ICOM's goal, then it has been achieved.
A little more compatibility ( according to the CCIR standard ) with other commercial devices would be
desirable at this unit price, as would a complete range of accessories.
1. Frequency response in the 2 MHz to 5 MHz range could be linearly boosted from 0 to 1 dB.
2. Audio carrier level is 6 dB too low and should be boosted.
3. ICOM designers chose a poor component for the connectors ( audio-video input and audio-video output ). The 4-pin 3.5 mm ( 1/8 inch ) jack (of which only 3 are actually used) doesn't always make proper contact. Once again, they skimped on connector quality for such a cheap €4,000 device.
This defect was noticed in both devices and both jacks !! - They could have used something different, with more safety, right ?
How does this defect affect operation ? - See here in a short 19-second video...
https://www.youtube.com/watch?v=ZFj600cUrG4
4. The scope of delivery is missing an original ICOM AV cable with the correct 600 ohm and 75 ohm impedance for the output and input jacks, respectively; then perhaps there would have been less of a problem with the contact.
Additional test with smaller bandwidths, 10MHz FIL2 and 5MHz FIL3
- 1.jpg (68.11 KiB) Viewed 7174 times
- 2.jpg (69.96 KiB) Viewed 7174 times
In the FIL3 5MHz BW position, the audio subcarrier can only be used up to 5.5MHz!!!
Higher carrier frequencies ( such as 6.5, 7.02, and 7.20MHz ) do not pass through the filter.
From approximately 3.5MHz onwards, the frequency response is severely cut by the filter, and the color subcarrier only partially passes through. The higher audio carriers are completely eliminated by internal filters and are therefore inaudible.
And below, the distance between the carrier and the audio carrier is also measured, for various signal BWs with the audio carrier set to a fixed 6.5MHz ( Info: with the 17MHz BW FIL1, the audio carrier should be approximately -20dB ).
- 3.jpg (246.08 KiB) Viewed 7174 times
Final Word:
A test technician will certainly find many errors in the IC-905's analog signal processing that do not comply with the standard ( some of which can be corrected by software changes – it just requires goodwill on the part of the ICOM technician/programmer ). BUT for most TV amateur radio operators, only a stable color picture is important ( which is also present here ) to conduct QSOs; they don't have the measuring equipment to check the video signal. If that was ICOM's goal, then it has been achieved.
A little more compatibility ( according to the CCIR standard ) with other commercial devices would be
desirable at this unit price, as would a complete range of accessories.
Last edited by oe7dbh on Tue Apr 22, 2025 2:11 pm, edited 7 times in total.
Re: IC-905 - Commercial FM ATV Transceiver
Some IC-905 owners may be wondering:
Would it be possible to compromise so that our picture can be seen clearly on other FMTV devices? For example, a satellite receiver, as is currently no longer in use ( some of them also have the option of 16MHz BW, e.g., the PACE MSS100 series ).
Configuration: IC-905 17MHz BW FIL1 ---> Satellite Receiver 16MHz BW
Below, I'll show you what to adjust on the IC-905 transmitter settings so that your contact partner gets a relatively usable picture.
Situation: You're at home or portable, perhaps currently in an ATV contest with your IC-905 ( regardless of the band frequency ), and you meet someone on the radio who wants to have an ATV QSO with you, but doesn't have an IC-905 themselves, but can receive you with a satellite receiver. You send them a video signal, and once the correct reception frequency is set, they will also see this signal, like this...
On his TV or monitor, the picture is visible in color but very dark, dull, and difficult to view ( Why? ...because the monitor requires 1Vpp - the standard value ).
What can you do at this time as a transmitter to improve his viewing ?
It is possible to increase the video gain, which simultaneously results in better modulation of the RF carrier, from 50% to 78%, and this is how it is done...
The received picture is still not good enough but significantly better, after that it looks like this...
This also works in an emergency.
For a permanent solution, there are only two options:
1. Insert a video amplifier ( with a 1Vpp output ) between the satellite receiver's video output and the monitor.
2. Perform technical intervention on the satellite receiver, increasing the video gain to 1Vpp ( if possible ).
Vy 73 de OE7DBH
Darko
For any translation errors from the original in German https://oe7dbh.blogspot.com .....please blame Google Translate
Would it be possible to compromise so that our picture can be seen clearly on other FMTV devices? For example, a satellite receiver, as is currently no longer in use ( some of them also have the option of 16MHz BW, e.g., the PACE MSS100 series ).
Configuration: IC-905 17MHz BW FIL1 ---> Satellite Receiver 16MHz BW
Below, I'll show you what to adjust on the IC-905 transmitter settings so that your contact partner gets a relatively usable picture.
Situation: You're at home or portable, perhaps currently in an ATV contest with your IC-905 ( regardless of the band frequency ), and you meet someone on the radio who wants to have an ATV QSO with you, but doesn't have an IC-905 themselves, but can receive you with a satellite receiver. You send them a video signal, and once the correct reception frequency is set, they will also see this signal, like this...
- 1.jpg (85.53 KiB) Viewed 7162 times
What can you do at this time as a transmitter to improve his viewing ?
It is possible to increase the video gain, which simultaneously results in better modulation of the RF carrier, from 50% to 78%, and this is how it is done...
- 2.jpg (80.62 KiB) Viewed 7161 times
- 3.jpg (85.21 KiB) Viewed 7161 times
For a permanent solution, there are only two options:
1. Insert a video amplifier ( with a 1Vpp output ) between the satellite receiver's video output and the monitor.
2. Perform technical intervention on the satellite receiver, increasing the video gain to 1Vpp ( if possible ).
Vy 73 de OE7DBH
Darko
For any translation errors from the original in German https://oe7dbh.blogspot.com .....please blame Google Translate
-
WiSi-Testpilot
- Posts: 6
- Joined: Sun Nov 24, 2024 10:17 am
Re: IC-905 - Commercial FM ATV Transceiver
Hello Darko,
thank you for your interesting review.
Since I don't have an ATV repeater nearby, I'd like to do some tests with a portable system soon, when it's warm outside. My initial tests showed that transporting and setting up and dismantling the many components is very cumbersome. Therefore, I mounted the two IC-905s on plywood boards. At the moment, everything is disassembled again because the boards were painted red. (I love colors.)
My antennas have adapters so I can attach them to photo tripods.
The pictures with the IC-905 show the QO-100 center beacon.
Best regards,
Wilhelm
thank you for your interesting review.
Since I don't have an ATV repeater nearby, I'd like to do some tests with a portable system soon, when it's warm outside. My initial tests showed that transporting and setting up and dismantling the many components is very cumbersome. Therefore, I mounted the two IC-905s on plywood boards. At the moment, everything is disassembled again because the boards were painted red. (I love colors.)
My antennas have adapters so I can attach them to photo tripods.
The pictures with the IC-905 show the QO-100 center beacon.
Best regards,
Wilhelm
- quickly.jpg (588.29 KiB) Viewed 6469 times
- Plywood.jpg (609.7 KiB) Viewed 6469 times
- 2p4GHz-Antenna.jpg (415.98 KiB) Viewed 6469 times
- coming-soon.jpg (641.32 KiB) Viewed 6469 times
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WiSi-Testpilot
- Posts: 6
- Joined: Sun Nov 24, 2024 10:17 am
Re: IC-905 - Commercial FM ATV Transceiver
Hi,
this is my Antenna Forest (for the IC-905)
Best Regards
Wilhelm
2 m / 70 cm Logper, 1.2 GHz, 2.4 GHz, 10 GHz Slotantenna
RX, see below, 10 GHz, Offset-Dish with LNB for QO-100 RX and 2.4 GHz Helix for QO-100 TX
RX with SDRplay, Mele Quieter PC, Dual GPSDO for LNB and SDRplay, 2000 NITS Display
I am using this RX to demontrate Meteor-RX on the GRAVES QRG of 143.05 MHz
For Meteor RX details you may look for Wilhelm Sicking Meteor.
this is my Antenna Forest (for the IC-905)
Best Regards
Wilhelm
- 4Antennas.jpg (1.37 MiB) Viewed 6072 times
- Dishes.jpg (1.36 MiB) Viewed 6072 times
- RX.jpg (649.54 KiB) Viewed 6072 times
- RX1.jpg (487.03 KiB) Viewed 6060 times
- 6-Kleiner_Meteor.jpg (812.99 KiB) Viewed 6057 times
For Meteor RX details you may look for Wilhelm Sicking Meteor.
-
WiSi-Testpilot
- Posts: 6
- Joined: Sun Nov 24, 2024 10:17 am
Re: IC-905 - Commercial FM ATV Transceiver
After a short vacation, the devices are now installed.
I also added solid N connectors to prevent damage to the SMA connectors in the field.
73 Wilhelm
I also added solid N connectors to prevent damage to the SMA connectors in the field.
73 Wilhelm
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