First things first. I love it even though it does have some issues I need to address. As others have said, it is a fantastic bit of feature-rich kit for the price.
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Received it in the UK on the 4th of May, a little ahead of when I thought it might be shipped. No VAT or charges from the carrier have been requested.
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The date of this post is 22 May 2022 and the software versions in the shipped version are: display: v1.06 and main board v3.052.
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It is running nicely on two batteries. On RX: current drawn is 460 mA. On TX: at 100 drive into a dummy load it is 2.6 Amps.
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Power out (20m 14.035 MHz) Vbat = 7.7 V
Drive = 100 Pwr = 7.00 Watts?
Drive = 80? Pwr = 5.00 Watts
Drive = 50 Pwr = 2.65 Watts
Drive = 30 Pwr = 1.00 Watts
Drive = 25 Pwr = 0.69 Watts
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At Drive = 100 above, heating and power loss of the rx components is 3.85 watts; transmitted power is 7 Watts and the battery is supplying 20 watts.
The box is dissipating 13 watts when transmitting, so it is going to warm up. I'll try and get an estimate of the thermal impedance of the box to get an idea of how long it is wise to transmit, particularly with FT8. My morse is so slow and gappy it is not going to be a problem!!
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The morse keyer issues are already noted, and I find both the straight key and iambic modes unusable, but there is likely RF in the box causing issues. The question I am asking is this RF leak a likely cause of some of the keying issues when using a straight key or paddle??
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Using the automatic CQ (F1) facility as the benchmark for my investigation, it fails to complete a full 3x3 CQ call around 25% of the time. The code it produces is clean and easy to decode but it suddenly stops randomly without completing. Sometimes it is near the start, other times it is towards the end, and all points in between! I call this possible RF induce effect a truncated TX. The device continues to work normally after a truncated TX event.
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Applying some ferrites to the power cable from the cells gave a small improvement. This also made the straight key and paddle operation less glitchy.
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I also noticed the frequency of truncated TX incidents increased as the rear heatsink warmed up, hinting at some thermal component at work. Possibly, an inductor losing permeability as it warms??
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Another hint pointing the finger at leaking RF is when I touch and hold the heatsink during a transmission the frequency of truncated TXs goes down. Again, it does not eliminate them.
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I also tried short cables and ferrites for the morse keys, to no great effect.?
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FT8 also looked like its transmissions were being cut short. PSKreporter saw them but I didn't manage to complete a QSO. I need to do a bit more investigation here.
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The morse decoder works nicely. Its secret is twiddling with the IF setting and fine tuning into the blue bandwidth cursor. Once set it appears to work well in a range of conditions.
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I activated VNC so have a number of ways to access the machine. Could this additional overhead for the processor be a factor in the truncated TX issue? I feel it is unlikely.
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This is probably as far as I can go without taking the alan key to it and opening the case; which is the next step.
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Does anyone have any advice or guidance about tracking down this alleged RF issue? eg Where to Start? Applying some shielding?
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73 John
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HA3HZ