QRO or Not QRO? That Is the Question.

Some years ago I got myself a used HF power amplifier for 1kW.

The ACOM 1000 is regarded as a solid amplifier that holds it promises from 160m to 6m. That is also my experience.

However, with quite short distances to neighbours' houses, I am not quite comfortable with using it.

In fact I used it briefly on 10m with about 400W out. That was when the solar activity was still quite low.

Then I used it on 50MHz, also with about 3-400W. Tha antenna that could endure that kind of power was removed, and for some years I have used the V-2000 for (2m, 70cm and) 6m. Under no circumstances would I use more than 100W with that one, especially with  FM or digital modes like FT8. The capacitors will not stand that, and will be transformed into carbonized components.

So today the ACOM 1000, which has been on the radio shelf for a few years witout being connected to the power outlet (or a transceiver), was taken down from the shelf. I am probably going to sell it and get some more UHF/SHF equipment.

I will not abandon HF completely, but focus more on VHF/UHF/SHF, going a bit back to my old interests.

Over 30 years ago I was working a lot on 2m, 70cm and 23cm with relatively low power and decent antennas, and over 40 years ago I was working crossband 50 or 70MHz to 28MHz, and had a lot of fun with that. Now I want to try the even higher frequencies, too. probably mostly portable from hilltops, but also with a (very modest) station at home.

Mini #5: Test of low pass filters.

When I picked up the PM2B mentioned in #3, there were two 30MHz low pass filters included in the price.

Further, I had some older low pass filters, a 30MHz  and a 50MHz one, so I got them all tested today:

Out came the NanoVNA F (4" screen). The tests were made with a wideband calibration setting, so the absolute values are not perfect. 

All filters are in good working order.

This means that I now have three 30MHz low pass filters and a 50MHz filter, all fully functional:

The old one I have is a Yaesu filter with a 100W rating. I have had that for decades.

The second one is a Trio/Kenwood filter, 100W rating.

The third one was a bit of a surprise. An old Drake filter rated 1000W.

The fourth one is a BNOS low pass filter for 50MHz. No rating on the filter, but I suspect it is 10W or so. It is a much smaller filter than all the others.

I reckon that all those ratings will be reduced to about 50% of the stated rating if I want to operate 100% duty cycle modes, like digital modes, e.g. FT8.

I opened the 1kW filter, and all looks clean, a beautiful mechanical construction with silver plated coils and high power capacitors, likely silver mica types. Somewhere I have a PA for 10-11m that I suspect has poor harmonic suppression so the 1kW rated filter would likely fit nicely in a system with that one - if it has sufficient linearity for SSB. OK, as I mainly want to use it for CW that is not so much of a problem. FSK digital modes will also work nicely.

The other option would be using this filter with an old IC-M710 that can deliver 150W continuously.

I would hesitate to use this filter with my 1kW power amplifier, even if I use it extremely rarely.

Given that I paid <$100 for the two filters, including the 1kW one, as well as the not fully functional PM2B, I consider this trade as excellent.

I picked up more at that rally, more about that later, as it is a different story.

PM2B and Documentation, Mini Project #3 Goes on Hold.

Having seen the receiver working, if not very sensitive, and the transmitter part with no output at all,

I am putting the mini project on hold.

First of all because I have no proper documentation, no service manual, no circuit diagram and not even a user manual. If the set would have been in proper working order I would have found out how to use it, no problem.

Second, the transceiver is so old and primitive that I find the operation too cumbersome to my kind of CW operation:

1) The receiver preselector has to be readjusted when tuning through the band, and especially if changing band.

2) The transmitter needs 2 extra adjustments after tuning over the band, or at band switching.

3) The VFO tuning ranges are too large for my use. For CW I use about 100kHz at the bottom of each band. This model covers 3.5-4.0 MHz, 7.0-7.4 MHz and 14.0-14.8MHz. On 20m the useful tuning range of 100kHz takes up very little space on the dial.

4) I have not found any way of making an offset between receive and transmit frequencies, meaning that tuning to a proper receive tone offsets the transmitter frequency. Not practical on crowded bands. Modification necessary for this alone.

5) The audio output can only drive high impedance headphones (>1kOhm). Not very practical, as I do not have those any more, though I could use a piezoelectric earphone for tests, but I would not use it regularly. In order to use the set with ordinary modern headphones or earphones, or a speaker an additional audio amplifier is necessary. This already means that  another modification is needed in any case.

For these reasons I do not find the time to restore this radio to its original state a good use of my time.

So what to do now?

Modifications are needed in any case, if I should want to use the transceiver

The casing, with some shielding at the sides will still be useful. I can build my (partly) own construction in there, and make myself a multiband CW transceiver. This is no longer a mini project, but a much larger one.

I may try to find a replacement for the PA transistor, maybe the driver if necessary, so the transmitter can be shown as operational, but that is all. Apart from that, the PM2B mini project is on hold.

I do not have any lack of mini- or smaller projects, so life goes on.

Mini(?) Project #3. Ten-Tec PM2B.

After finishing the IC910 mod, here is the next mini project. This may be more than just a small one.

For a very low price I purchased two low pass filters (30MHz) and a non-tested Ten-Tec PM2B, so I do expect to have some activity before it is fully functional.

This is an old CW only QRP transceiver, officially with 1 or 2W out, and with a direct conversion receiver. The rig covers the 80, 40 and 20m bands

After cleaning the AF potentiometer and some slide switches I got it to draw about 30mA from a 14V power supply. The headphone output showed some noise, variable with the pot. It looks like the headphone output is high impedance. It does use banana plugs, not even a mini jack connector. Yes, this is very old.

With an external SSB receiver I found that the local oscillator is working and can be tuned correctly.

No external signal received yet.

No transmit output detected.

Also I have no documentation, not even a circuit diagram

It does indeed look like there is more work to do with this one

Looking into the casing I was not impressed with the build quality, with long flimsy wires running around, and it looks like it has been messed up somewhat.

This might end up being a larger project, essentially building a modernized version of a direct conversion CW transceiver with a digital VFO, and maybe with additional bands. We shall see what I do with this one.

If I do a total make-over I may add some shielding to the sides of the transceiver, as they are totally non-shielded.

Small Solar Power Update and More.

 The output from the solar panels has been very low the last several weeks, actually most of November.

I can hardly power my IC703 all day with the current solar input, even if it has improved a bit with the new MPPT charge controller. Some more solar panels should be mounted, but working outside in near freezing temperatures is no fun, so it may have to wait until spring, or if we get some mild and dry days. 

For just monitoring of the low HF bands 20,30,40,60,80m I should use the small Chinese built HB-1B CW transceiver when not at the radio desk, as it uses less power than the 703. The spectrum display of the 703, after all, is only useful when I am there looking at it ;).

With the current very high price for electricity I am looking more at reducing power consumption for the shack. The stand-by/monitoring system has been reduced at the moment until I can get some really low power gear built and/or put to use. Yes, there are options.

Then there is the heating. 

Recently I got an air-to-air heat pump mounted, and now it is finally connected to mains power in the correct way. Yes, I had the electrician here, and at the same time I got an outdoor connector made for charging my new "toy car" (yes, fully electric, running on batteries).

It does look like the mains power consumption is lower than last year, in spite of the fact that I used gas heating last year, and electricity to power the heat pump this year. It will be interesting to see how things will work when I get more solar power up and running. I am aware that going off grid is not possible with the garden I have available, especially in December/January, but any reduction of mains power usage is welcome.

More Radios on the Solar Power System.

The new solar charge regulator connected into the system, and more radios connected as loads. With the new controller I can manage around 600W peak power from the solar panels. Right now the panels provide only a maximum of 230W, so there is room for improvement, and I have some panels available

Setting this revised system up took a few hours. 

Radios connected now:

- IC-705 (running 6 - 80m with the new 30m "long wire" antenna).

- IC-7300 (running 4-6-10-(12)-15-(18)-20-40-80m with the dipole antenna)

- IC-703 (running 10 FM RX)

- FRG-100 (running 28200 Beacon RX)

- AR-8200 (running FT8 RX) will run continuously

- FT-8900 (running 70cm)

Total current consumption for all the above radios is about 2.7A, though not running all the time. 

Main radios for use will be the IC-705 and the IC-7300 and the FT-8900 for now.

As the system has been running all evening, the batteries indicate about 85% capacity left. Let us see how much sunshine is needed to get the power back up to above 95% tomorrow.

The IC-703, the FRG-100 and the AR-8200 are very inefficient as stand-by receivers and should be replaced with less power consuming receivers. Some of it should probably be home made, especially the FT8 receiver and the 28200 beacon receiver. This will likely reduce the total power consumption of the system by almost 1A - this could then be used for other  purposes, like a Raspberry Pi for running WSJT-X (FT8 monitoring).

In general, for general monitoring, the receivers should be really low power ones, as much as can be done 

I will need to test a Raspberry Pi 2 to see if it runs WSJT-X smoothly, and how the current consumption is.

Now I will have to see how this works as an independent power supply. I expect no problems from now, until October or November, but the few winter months will likely provide too little power from the solar panels. We shall see when that time arrives.

30m Wire Antenna Update.

 The 30m long piece of wire has found its place for a while.

The feed point is placed 2m high at the end of the out-house under an apple tree. It then goes up through the tree and lead to the second apple tree - the largest in the garden, then down to a smaller tree where the end is attached. Most of the wire is about 5m above ground, not particularly high, but definitely better than 1m above ground. 

The antenna now has a counterpoise added, about 50m of wire, about 2m above ground (and lower).

The system works nicely on 30m, and does not need a tuner when operating from 80 - 6m. On the resonant bands of the dipole, the dipole mostly works better, but on 20m in particular the wire gives signal mostly equal to the dipole. On 30m the dipole is useless, as it is not resonant at all, and the wire works nicely. A TZ station (Mali) was coming in nicely with up to S9 signals, but 5W was (as expected) not sufficient to break the pile -up. I will have to try again when signals are good, and less stations are calling.

The present set-up of antennas and transceivers for the 80 - 4m bands is now as follows.

IC-705:  Wire antenna, workable on all bands 80m - 6m.

IC-7300: Dipole working on 4,6,10,15,20,40,80m

IC-7600: The old R-6000 antenna running 10-12-15-17-20m, and the 6m part of the V-2000 antenna.

IC-7100: A vertical Sirio half wave antenna for 4m, mostly used for the local FM traffic.

HF Dipole Improved.

 My HF  dipole antenna for the IC-705 has been hanging very low for quite a while. Even then my 5W (mostly CW) challenge for the time of the year is on track.

Yesterday I made an effort to raise the feed point for the "inverted V"from 3.5m to just over 6m, just at the top of the largest apple tree in my garden. It can be brought higher, but for now it stays there, because some of the wires are somewhat entangled in the branches of the tree, and I have not yet un-tangled them.

The antenna is a Diamond make, 5-band dipole with one branch for 10 and 20m, and the other for 15 - 40 - 80m. It is likely that I can add 30m, maybe even 60m to this antenna, as I have some coils from a previous antenna. But this will be for later.

The result? It may be too early to say, but tests yesterday indicate more band noise on some bands.

First of all, the resonance frequencies are a bit high on the bands, mostly in the SSB parts of the bands, so the antenna is too short. I will have to "cut on" some wire (yes, I know, add a bit of wire, but I couldn't help playing with the words)

10m has not done too much, neither has 15m.

On 20m I have had clearly better signals, and it looks like more stations than before are coming back to my calls.

On 40m the band noise is clearly higher, as are the signals. Same for 80m. Some CQ calls on 80m gave a QSO to SP3CW last night.

This concludes the first stage of my antenna maintenance and improvement work, there is a lot more to do.

Solar Flare Observed Today.

 Around 1135 UTC today I observed a radio burst of noise on 14MHz. Going to 28MHz it was there, too.

I tuned into the GOES X-ray observations, and could follow the X-ray flare rising to a peak of M4.0 at 1139 UTC.

This is the first time in this solar cycle that I could follow a flare rising to a peak. I was just sitting in my living room when I heard the noise burst(s), so yes, it is a good idea to have a radio receiver running in the 14 - 30MHz range, just for that. I may build a simple DCRX with an audio amplifier, and maybe a visual monitoring (graph) for observing radio solar bursts. Preferably in a range with no other terrestrial signals (or noise from electronic devices). Oh, bother. Too many projects already ;)

This flare originated in sunspot group (AR) 2975 near the center of the solar disk. Looking at the movies this could be a full halo, earth directed, CME. Is there aurora in our near future? (the next few days).

10m. A Bit Less Active.

 The last few weeks 10m has been a little less active, but with a few days of high activity.

Solar cycle 25 is going rather well. At the moment the solar flux average is ligher than the official predictions, and has been so since the rise of activity started. There are, of course fluctuations, but at present the flux stays above 90 SFU, with periods of flux above 100, up to a peak of around 130. 

It still seems to be above the forecast, and it will be interesting to see how 10m and the other higher HF bands - and maybe even 6m - will behave as we approach the spring equinox.

The 5W challenge is on track. QSOs have been made on the bands 80-40-20-17-15m, and no more qre needed to fulfil the January goal. I will still try to make some more this month.

Idea Box: Single Band SDR Receiver With Old SDR Kits.

 

I have some old "single XO" SDR kits from Germany. I think I have some Softrock kits somewhere, too, they use discrete crystal oscillators.

As indicated they have a canned (DIP/DIL) crystal oscillator running on 4x the RX operating frequency, and the quadrature signals are generated using a 74AC74 dual flip-flop as divider/phasing, providing quadrature local oscillator signals on the receiver boards. 

The receivers cover only one small frequency range around the LO frequency, so with a 48kHz sound card interface the max bandwidth covered is a bit less than 48kHz. Sound cards with higher sampling frequencies can, of course provide more coverage, but the 48kHz sampling frequency is now ubuquitous in computer sound systems.

Here is the idea. Not particularly complicated or original, but this could make better use of those old kits.

My intention is to replace the fixed XO with a Si5351 module controlled by Arduino. This could be programmed in, say 10kHz steps for the LO, or indeed for a single frequency. There are several Arduino programs for making a VFO with the Si5351, so I should be able to modify the program to suit this purpose. 

I have one finished kit of this kind, and a few (2 or 3) not yet assembled, so I should be able to make simple SDR system for rarely changed frequencies, such as beacon frequencies or digital mode frequencies. All for monitoring purposes.

In addition, if all the wanted frequencies are within 45kHz, the system could be used as-is for a few frequencies, branching out the "stereo" I/Q outputs to more than one sound card/computer for dual monitoring, or alternatively, use a local webSDR server. 

I think that the splitting of I/Q signals is the simplest solution to this, though.

The single frequency can be generated by a suitable XO, if that cannot be found, the Si5351/Arduino can be used to generate a single frequency.

I do have a finished kit for 80m, and I will check if I have a suitable XO for covering the FT8, JS8, WSPR/QRSS frequencies. It does look like a 14318kHz XO is usable for covering these frequencies with the 48kHz sampling frequency, although JS8 could be a bit tricky.

Major Solar Flare and Some Good High Band HF Propagation.

 The sun has done it again.

After more than a week with good strong solar activity, solar flux up to over 100, the activity jumped up to about 110, the 10m band is pretty good with openings detected, using FT8 as a monitor, to all continents.

After several days of solid solar activity, yesterday one of the sunspot groups unleashed an X-class solar flare, X1 - the highest category. This is not, by far, the strongest solar flare recorded, that happened in 2001, when the X-ray sensors on the NOAA satellites were saturated. Actually, I was watching the website when the flare started, and grew and grew in intensity, then the graph flattened at the X17, and I thought that the flare had finished, but when the graph stayed at X17 for more than 10 minutes I realized that this was much more than X17. It was later estimated to have been at the X28 level, and that is the official record. An X28 flare is 28 times stronger than X1.

Looking at the website it was clear that the sunspot group had already produced several major - M-class -  when it erupted, and there is still activity in the sunspot group. When it erupted there was a short wave black-out - SID (Sudden Ionospheric Disturbance) on the day time side of Earth.

When I received the mail from Spaceweather.com I took a look at the short GIF of the flare in UV light, and there was a clearly visible darkening of the sun spreading fast from the flare site. This is something I had not noticed before, so I had to watch it a few times to be sure that it was not my imagination. But no, this was definitely visible.

The X1 flare from yesterday happened just when the sunspot group was close to the center of the sun's disk as seen from Earth, so the CME (Coronal Mass Ejection) is moving towards us. The expected impact time is likely to be around the night Saturday to Sunday, although the timing can be off.

What does the impact mean? If the direction of the magnetic field is "correct" we may get good mid-latitude aurora activity, with visible, or at least photographic aurora and a strong geomagnetic storm - the alert says up to the G3 level, if it is not, we get a lesser geomagnetic storm. 

What does this mean for HF propagation? As I see it the CQWW SSB contest this week end might have very poor propagation, maybe even with periods of the bands almost closed.

Longer term, if the solar activity stays at this level, approaching winter, we could have some strong day time openings on the high HF bands 15 - 12 - 10m. I would not be surprised if we get strong F2 openings between Northern Europe and the East coast on North America - if the geomagnetic activity does not get too high. I will not be surprised if we will have good 10m opening all the way through winter and well into the spring here. It may disappoint, who knows?

Ground connection for the Mini Whip. RX Test.

 I have a ground rod on the Mini Whip now. Not too far into the ground, about 60cm/2ft. Hammering a 2m (8.5ft) ground rod is tricky without the right tools ;)

The results are interesting:

A relatively detailed review was done today, by dialing slowly through the bands. Starting downwards from around 18MHz indicates that the sensitivity/SNR has improved reception on frequencies from about 1.8MHz up to 18.2MHz, maybe higher.

Medium wave is not bad, with signals on essentially every channel in the whole band, with a reasonable SNR, probably increased sensitivity.

NDB band appears noticable worse wrt SNR, possibly partly due to overload from MW stations in the evening, but noise level seems to have increased.

LW seems OK, not spectacular.

VLF (<100kHz) seems more sensitive, but with more noise. possibly due to overload of the RX. 

A different Mini-Whip with a real whip antenna (1 - 3m long) might improve sensitivity on VLF/NDB bands, but should probably have a low pass filter with a 3dB cut-off frequency of 530kHz. Because a thin whip mounted low is not too visible I might add this to my antenna farm, just to see how it works. If it works well I can make a permanent installation.

Because the Mini Whip is very broadband it may be an advantage to make some filters in any case, possibly as follows:

Low pass with 150kHz 3dB point, for the 136kHz amateur band and "VLF" reception.

Band pass with 150kHz high pass and 530kHz low pass, mainly for the NDB/marine bands and 472kHz amateur band.

MW band pass with 530kHz high pass and 1700kHz low pass.

MF band pass with 1700kHz high pass and 3MHz low pass, mainly for the 1.8MHz amateur band.

HF band with 3MHz high pass filter.

If I get all working nicely I may make a (set of) distribution networks, possibly with switches for the different receivers.

Yes, I like monitoring a lot of frequencies I do have some receivers, everything from purchased amateur equipment to portable transistor radio(s) with external antenna input(s), and, of course some SDRs, and some simple monitor receivers (e.g. a Pixie kit for 40m), and some that I may build. At some time I have been monitoring (audio or data) on 14 different frequencies simultaneously, part of it as monitoring propagation, and I expect this record to be beaten ;)

This is also part of my intention to make a contact on as many bands as possible with (at least partly) home made equipment.

Active Receive Antenna: The PA0RDT "Mini-Whip". First Experiments.

 A little while ago I purchased a Mini-Whip set (the outdoor unit and the bias-tee) from Chine. Quite inexpensive, and now when the weather is improving (some days, it is April, after all) I started an experimental set-up.

I was aware that I should avoid noise from entering the antenna via the outside of the coax, so the first step was using a common mode choke (CMC) at the antenna, with a low cost (green) EMI toroid from China.

The antenna is mounted on top of a 4m long telescopic fibreglass mast, intitially just attached using duct tape, placed at a relatively low noise point in the garden with more or less optimized distances to all surrounding houses. This is sufficient for the testing and can be changed later. The power supply is a battery, just to avoid noise entering directly the system via mains power.

The result was quite disappointing, but not entirely unexpected up to 7MHz there was a substantial noise floor, reducing the signal-to-noise ratio (SNR) when compared to a multiband dipole I have in the garden, and the noise level on medium and long wave (MW, LW) was killing all signals less than S9 Even then, and this was encouraging, more than half of the MW frequencies showed audible stations before sunset.

Next step: Adding a "SW" CMC just next to the bias-tee. This was using a FT 240-43 toroid core with 2x10 windings of RG-174 coax. Progress: The noise was reduced on SW, now the Shannon VolMet on 5505 was audible with a decent signal, not quite as good as with the dipole, but a definite improvement. MW was still quite noisy, and LW not good enough. Very few NDBs (Non-directional beacons, mostly situated at airports) were audible in the 300 - 500kHz band. signals on 472kHz were still drowning in noise.

Yet another step: A second LF CMC was added (one more of the green Chinese toroids) was added, making MW quite usable, though not perfect.Several NDBs popped out of the noise, and with better filters in a receiver there would probably be many more to find. The usable frequency range was extended to 400kHz up to at least the 30m amateur band at 10MHz. The Shannon VolMet now has a SNR comparable to the dipole. Good progress.

This is the state of affairs at the moment. There is still too much noise for my taste, but at least I can work on removing noise coming from my own house.

There is more to try:

1) adding a second (MF/SW) CMC at the antenna. This is not too difficult.

2) Adding a ground connection directly to the ground of the Mini-Whip PCB, "bypassing" the CMCs at the antenna.  This will take a bit longer because good weather is necessary if I want to solder outdoors. As an alternative the antenna could be dismounted and the soldering could be done indoors. Further, a 2m ground rod should be hammered down.

Still more to do with this receive antenna system, but it is a decent start

IC-703 Modification.

For the first time in almost 2 years I have been traveling (more than about 100km from my home) for a bit less than 2 weeks, and I am back now. This was a non-radio-related round trip From my home near Copenhagen through Northern Germany, The Netherlands and Belgium, then to Paris. On the way back via Köln (Cologne). Last year I spent getting rid of a colon cancer, and I am now free of it, just going to control visits every few months.

Today I modified my old IC-703 for receive output/input. Will likely use that TRX for 10m with aux RXs for 10/11/12m propagation monitoring, using the TRX with the 10m PA running about 200 - 250W CW or about 150W FT8. Should work nicely.

Why do a modification like that ?
Well I wanted to be able to add some kind of spectrum/waterfall display, and possibly use the same antenna with several monitor receivers, e.g. beacon watch, FT8 watch etc.

I was using a kit purchased for doing the trick on a IC-7300, but decided to try it with this one first.

The mod took a bit of filing off the outward side of the new adapter and filing a bit of the bottom cover, and removing the connector for the external ATU control. The external control is not necessary as long as the built-in tuner works (or is not needed at all).

It now fits nicely into the casing.

System check of the RX shows that it is working nicely in through-mode.

It is likely that the modulation circuit will need an equalizer, because the reports on the modulation are not good enough. Initially, I will check the adjustment of BFO and SSB filters.

Second use for this low power TRX could be driving a transverter to 4m, including RX output for AUX RXs, such as spectrum waterfall.

Using the PA for both HF and 6/4m transceivers.

I have a IC-7300 covering HF, 6m and 4m, and a IC-7600 covering HF and 50MHz. I would like simultaneous use through the PA of both transceivers to a R-6000 antenna and a 6m 1/2 wave antenna.

How to proceed? Here is my idea. Between the radios and the input of the PA I can use (lazy as I am) a commercial diplexer, like the CF-360 from Comet or the MX-62 from Diamond.
The problem with using those at the output of the amplifier is the limited power they can handle. 600W PEP or about 200W continuous. Not exactly fitting for the 1kW capability of the amp.
Looking a bit around on the net I found this : https://www.ka6wke.net/hf-vhf-diplexer , describing the use of a IC-7300 with an HF antenna and a 6m antenna with a home construction diplexer. There is a design that I could use, albeit with components capable of withstanding the higher power.
What about 4m ? At the moment of writing this, the power limit for 4m in Denmark is 25W, so the PA is not really necessary. If the limit goes up, I might think of a modification to the existing PA, or using a second transceiver for 4m and building a separate amplifier for 4m.

Next step is to find those components.

At the moment the amp is running low power, 200W, with a CF-360 at the output, connected to a vertical 1/2 wave 6m antenna, at the VHF port and the R-6000 at the HF port.

Now, here is the question some will ask :Why use a separate antenna for 6m when the R-6000 does 6m, too ? I have compared the two antennas, and I find that the 1/2 wave antenna for 6m performs far better than the R-6000 on that band. Further, since I do not intend to set up a HF beam, but at a later stage I do intend to have a small 6/4m capable of accepting the full power of the amp, so here we go !
I may design some high voltage capacitors , maybe made with PCBs, if I can not find some suitable for the 1kW filter I prefer to design for higher power than I intend to use, so I can avoid burnt components and/or equipment.

Oh, Boy ! Yet another project added to the pile ;)