Recent content by Guineafowl

The smart TV can use the 5 GHz, but doesn’t as it has a direct ethernet cable connection. Router is about 6m from the tv, but with no line of sight. I’ve restricted the 5 GHz channel width to 20 MHz anyway, but such is the joy of intermittent faults, I’ll have to wait a week or so to see if...

I was having trouble logging in to the router gateway, but am in now. It uses 2.4 and 5 GHz channels. The 2.4 channel width is already set to 20 MHz. The 5 is set to auto (20/40/80 MHz), but has an option to force 20 MHz only. The bluetooth remote apparently uses the 2.4 GHz band, so would...

I can’t see much from the outside. No access panel for the power board so it’ll be a case of spudging horrible plastic clips all the way around to get inside.

Model UE55NU8000T, with a ‘smart’ remote operating on Bluetooth (except for the power button, which is IR) and a normal one, which is all IR. Intermittent faults: - Loses BT pairing with the smart remote. Sometimes will not re-pair unless the TV is unplugged/plugged at the wall. Always works...

The Rigol has arrived, and I’m just getting familiar with it and waiting for the 100x probes. It’s very nice to be able to capture waveforms. For example, I can now tell that my ESR/inductance meter measures both quantities at 69.1, 7.2 and 1.8 kHz, just by rolling a waveform, freezing and...

If you insist, then. I’ve ordered the Rigol DHO804, which has some good reviews. Having four channels on the Fluke has been helpful, eg when scoping a switch-mode power supply - I can watch the feedback, oscillator, chip power supply and output voltage all at the same time. Also, two cheapish...

Yes, like most small-time machine users, I’ve set up the VFD and hoped for the best. This one’s been in use for a year; I have other old machines on VFDs for years. The risk of insulation failure is apparently a real one, so it’d be nice to make a simple, cheap filter for peace of mind. Good...

This, a 1961 Beaver VBRP:

Ok. I have to be careful about the selection of the resistors - running a VFD with the output open circuit can ruin it. Using high-value resistors may have the same effect. The motor windings (in delta) have a dc resistance of 6##\Omega##. This is one winding in parallel with the other two in...

It was the multimeter measuring. The supply neutral is referenced to earth at the pole transformer, probably around 100m of cable length away, overall: Looking again at the scope shot in #29, I was able to move the trace down and see the peak of that waveform, which would be +340V. This should...

Thanks, the line trigger trick worked better, but the trace is either incomplete or slowly redrawn, presumably due to variations in line and VFD output frequency. Not camera-friendly. This is a typical VFD topology. In my case, the input is single phase, and the motor in delta. It is...

But the VFD isn’t a step-up type - the output is three-wire, effectively delta, 3ph at 240 Vrms phase and line voltage. It should, as I understand it, take the form of 340 Vpk (680 Vpk-pk) pulses of varying width. Could it be that the very thing we’re trying to get rid of, voltage overshoot and...

No neutral. The VFD output is 240 V P-P. How come it displayed the real 240 V mains ok?

Try as I might, I couldn’t get the scope to trigger properly. This is channels 1 and 2 on U and V terminals of the motor, scope set to CH1-CH2, 10x probe setting. The changing image was hard to get on camera: Next the filter circuit was added: However, the VFD threw an overcurrent error on...

Thanks! I did have CT surgery about ten years ago. This is more a side-issue of deep thenar pain, maybe tenosynovitis or basal joint arthirits. A career-ender (and guitar-playing ender) for me. The electric fence trick is good neuroscience - gate control, endorphin release - and the basis of...