FT8 Monitor Now On 6m. And IC-X02 update.

The receiver in the portable (handheld) CB radio, a multimode from Albrecht, I was using for 10m FT8 monitoring looks like a very poor choice. I have used it for 10m FT8 monitoring for a while, and while it does work, it is not very good.

If I will venture a guess, it is due to a poor performance of the PLL circuit. The FT8 signals look very wide, so I suspect excessive sideband noise.

The advantage was a relatively low power consumption, less than 120mA @ 12V. Good enough when using solar power.

The other reason to change is simply the season. It is the season for sporadic E (Es) propagation on the lower VHF bands, and occasionally on 2m.

So, for now I picked one of my FT817s to set up for FT8 monitoring. It does have a higher power consumption, 300-400mA @ 12V, but especially in the summer time it is working perfectly for 24/7 monitoring. The two inputs of the FT817 mean that I can also connect an HF or VHF/UHF antenna to the RX, and use it for FT8 monitoring for everything from 160m (630m?, 2200m?) to 70cm. One band at a time.

The 6m receive input is connected to the 6m part of my R6000 multiband HF/6m vertical, via a HF/6m diplexer.

This is the least efficient antenna I have for 6m, so if I can get signals on that one, it shows that 6m may be sufficiently open to make contacts with my station.

Small update on the IC-X02 transceivers:

As I decided to use those mostly for monitoring SSB/CW on 6m/2m/70cm, I decided to leave the two IC202s as they are, only making the modification of the power plug.

The 6m one got a cable through the hole for the power supply plug/cable, so an external power supply only is used. I removed the battery connection inside the battery compartment, so it can be used for experiments like adding a CW filter and other niceties. For the 6m band monitoring I still need to build an amplifier/power splitter, so I can use the monitoring on at least 3 receivers: 50313USB for FT8, 50100USB for SSB/CW and 515xx (or so) for FM monitoring.

The IC202 #2 has a modified connection to the power plug, so I can use my standard cables/plugs for this one.

The IC202 #2 (heavily modified) and the IC402 still need power plug connections modified. The IC202 #1 also still needs some detective work to see what the modifications are doing. One is a switchable audio CW filter, so that is a start.

A Bit More on the IC X02s and Propagation Monitoring.

 I have made some tests of the two IC202s, the IC402 and the IC502.

These are the preliminary results, essentially my notes after testing:

1) Ancient (my first) IC 202 #1 (2m):

Some modifications were made:

- Antenna connector changed to BNC and moved. PL connector disconnected.

- Telescopic antenna removed.

- Audio CW filter added with switch at the top. In working order.

- unknown veroboard with ??? circuitry connected to main board main connector.. Detective work needed.

- Some relay circuitry and ???. Detective work needed.

Most of the mods are in the original battery compartment, replaced with a copper clad PCB

- This one looks like it has a connector for an external VFO. Could be useful making a more stable LO. Need to find the appropriate info if I want to build/connect one.

- TX out CW: 30mW Detective work needed.

Use as back end for transverter ot down converter?, or just 2m monitor (144.300)?

2) Also a quite ancient IC 202 #2 (2m):

- PL connector replaced with N connector (good move).

- Some Veroboard modification at the mainboard main (long) connector. Detective work needed. Looks like RF output power control circuit. 

- This one also looks like it has a connector for an external VFO. Could be useful making a more stable LO. Need to find the appropriate info if I want to build/connect one.

- Zero out put in CW. Detective work needed.

- Still needs a check.

Use as back end for transverter?

3) IC 402 (70cm):

- quick check, and seems to be in working order.

- Need to change power connector (I do not have any "male" 3-pin-plus ground connectors for power cables, so will likely let a filtered cable out through the power connector opening.

- TX out CW: just under 3W @ 12.5V Looks OK.

Build external VFO? (e.g. in the battery compartment)

4) IC 502:

- Checked the IC502. VFO looks rather unstable. Contact spray helped with RIT and a bit with the fine tuning. Still not quite good, but could be used for "fixed" frequency monitoring, e.g. +/-50.100.

Should probably (long term) be replaced by a Si5351 synthesizer w/Arduino control (e.g. in the battery compartment) 

- Need to change power connector (I do not have any "male" 3-pin-plus ground connectors for power cables, so will likely let a filtered cable out through the power connector opening.

- TX out CW: 2W @ 12.5V Looks OK

Final result: 

All radios seem to work fine in receive mode (a bit more testing, and maybe alignment, will be in order.

The '402 and the '502 appear to work nicely overall.

The two '202s need some work to get TX working properly again. Those could still be used as monitor receivers without problems.

Epilogue:

I do have some FT817s. One with a blown PA, the three others okay. Here is the thing:

I want to do as much general monitoring as possible on solar power. This means minimizing power consumption.

The IC-X02s use about 100mA @ 12.5VDC

The FT817s use 3-400mA. 

So for monitoring, I could power 3 or 4 IC-X02s for the power that the FT817 draws. Yes, I want those up and running.

The IC-X02s will not be suitable if I want to monitor digital modes like FT8. for that I need to use the FT-817, maybe later build some simple crystal or PLL controlled receivers.

Yes, still far too many things to try out.

Ancient Icom Radios: IC202 etc.

As I am trying to get more radios up monitoring different frequencies, here are a few things to consider:

First of all, building kits, and possibly modifying some of them are good for monitoring HF frequencies is a good idea.

Second, of all, for VHF monitoring, using the modern radios (with spectrum display etc) for all day monitoring, even when I am not close to the radios, seems to me like a waste of energy, as many of them use more than 1A, just in RX mode.

Enter the old IC-202. I have two of them, one heavily modified (I need to determine what I did with them), one that I got later, and it seems to be in order. Those are good for some SSB/CW monitoring, where the exact frequency is not all to critical. The great advantage when using them for all day monitoring, when in the house, but not near the radios, is the much lower power consumption. 

The IC202 is a 2m VXO controlled SSB/CW transceiver with max 3W out, and a stand-by RX current consumption of less than 100mA.

I have another old ICOM in the same family: The IC-402 for 70cm. About 100mA consumption on that one, too. Good for 70cm monitoring. When checking that one, I found that I had not removed the old Alkaline batteries, but the leak did not appear to have caused damage. 

The 402 could also be used as base receiver (or even transceiver) for down converters or transverters for microwave. 

The fourth transceiver found in the cupboard is the IC-502 for 6m. It covers 50-51MHz with a VFO, also with a current consumption of about 100mA. This one, I suspect will be a bit tricky to tune to the correct frequency, due to the larger coverage. For monitoring I may use one of the other transceivers to provide a "tuning aid".

I am trying to run more and more of my operation on solar power, so the power consumption will be critical, especially in the winter time when very little sunshine is available. Reducing the stand-by RX current to about 350mA for 6m, 2m, 70cm all-day monitoring is a big step forward, compared to several amps used by the "big" radios, just for general monitoring of 50/144/432MHz.

These radios will likely need to be checked and aligned, so here is another project for the late summer to winter activities.

Yes, the current solar power system still needs to be improved for winter use. Still, I expect to need to need topping up the battery storage in the months of December and January. That is okay, if I can use the station on (mainly) solar power most of the year.

Update: Did a check of the IC-502. 

The VFO frequency is rather unstable and very sensitive to very small movements in the casing.

Volume control and RIT/fine tuning (all with potentiometers)got some contact cleaning (without residue after cleaning), and so did the on/off/light switch.

The volume control and the RIT work perfectly now, as does the on/off/light switch.

I suspect that the fine tuning pot could get a better cleaning, as it still shows some roughness. This may require some disassembly of the set.

For now I will leave the set on for a while with low supply voltage (8V in place of 13.8V), to see if the electrolytic capacitors are in working order

I also have to remove the power connector, as I do not have a corresponding plug for the 3-pole connector mounted.

A modification for feeding power is needed. Probably using a cable soldered directly into the transceiver

For now, after a longer power-on test, I think that this set can be used as a monitor receiver for, say, 50.100MHz, the general CW/SSB calling frequency.

Current consumption with moderate AF out was about 90mA, as I expected.

For 50MHz general propagation monitoring I expect to use the 50MHz part of my R6000 for now. With a modest amplifier indoors, and a satellite/TV power splitter, I should be able to use that antenna for this, with at least two receivers connected:

- The IC-502 for SSB/CW

- The old Tokyo HyPower handheld for FT8 monitoring.