Test Equipment Anonymous (TEA) group therapy thread

[Zucca]

Make certain that the µinverters are tested for EMI/RFI as a system, not in isolation without the antenna lengths that typically occur in an installed system.  The noise floor from a typical contractor-installed µinverter PV system must be seen on the SA to be believed... Here, both the aviation authority and the military have issued disconnect-and-dismantle orders to several home owners that had "professionals" install systems, sadly enough a bit too close to "something important".

Twisting the cables and screening the inverters apparently has made wonders in some installs, but they remain a nuisance.

Holy shit, I live 3 minutes driving away from a small airport. Your post could have avoided some aviation problems in USA,SC

I have now the crazy idea to move all the µInv inside the house in the attic, that would make it easy to put them in a shielded box.
The radiation is coming from the long AC lines and not from the DC line from panel to the µInvs, I imagine....

[mnementh]

@Zucca get them while you can. You can always install a battery later.

Unfortunately I am not in a rush, here my plan:

1) Install first PVs in every possible inch on my roof and my south facing home wall. Microinverters of course.

Make certain that the µinverters are tested for EMI/RFI as a system, not in isolation without the antenna lengths that typically occur in an installed system.  The noise floor from a typical contractor-installed µinverter PV system must be seen on the SA to be believed... Here, both the aviation authority and the military have issued disconnect-and-dismantle orders to several home owners that had "professionals" install systems, sadly enough a bit too close to "something important".

Twisting the cables and screening the inverters apparently has made wonders in some installs, but they remain a nuisance.

I never could understand why these systems seem to get away without the same NEC (or similar regulatory agency) requirements for conduit on any exposed runs as if they were connected to a mains, which in many cases they actually are (at the other end, yes... but still  ). I've seen horror shows on yoobToob where they're connecting everything with exposed cables and wirenuts and similar shit...? Well, maybe just the panels, I'm not sure now... but at ~36V up to ~45V open circuit voltage on some of the bigger ones, that's still hardly safe to treat so cavalierly.  and ½...

mnem
*tzzzzzzzt*

[mnementh]

Make certain that the µinverters are tested for EMI/RFI as a system, not in isolation without the antenna lengths that typically occur in an installed system.  The noise floor from a typical contractor-installed µinverter PV system must be seen on the SA to be believed... Here, both the aviation authority and the military have issued disconnect-and-dismantle orders to several home owners that had "professionals" install systems, sadly enough a bit too close to "something important".

Twisting the cables and screening the inverters apparently has made wonders in some installs, but they remain a nuisance.

Holy shit, I live 3 minutes driving away from a small airport. Your post could have avoided some aviation problems in USA,SC

I have now the crazy idea to move all the µInv inside the house in the attic, that would make it easy to put them in a shielded box.
The radiation is coming from the long AC lines and not from the DC line from panel to the µInvs, I imagine....

Ehhhhh... ever looked at the power from your PC's PSU on a scope while it's running vs when it's not? The VRMs generate and pass through from the CPU oodles of noise that you can see inside the PSU when it's working hard.

Hmmmm...

Now that I think of it, would be a interesting experiment to see how much of that is actually the VRMs and how much is the processor on a modern system... maybe a pure resistive load on the VRMs to see...?  Or maybe monitor noise fed back to the battery on one of these high-HP gaming rig laptops...

mnem
 

[mansaxel]

I've seen horror shows on yoobToob where they're connecting everything with exposed wirenuts and similar shit...?

If it'd only been Wagos!

No, seriously; that's not how it's done in Yorrp; there are special high-voltage watertight connectors and special double-insulated cables for chaining panels.  (image is clickable for wikipedia article)



Micro-inverters is different, of course, but they too need connecting out to the grid, and there are special connectors for that too.

[med6753]

Local CL has this Heath SB-301 for $90. Made me pause for a moment then dismissed it. Why? Well, it was a kit. Build quality is definitely a crap shoot. And who knows if it ever worked properly when it was complete. That's a definite consideration. I'll pass but I did give it some thought.



I've seen worse....much worse.

[mansaxel]

Make certain that the µinverters are tested for EMI/RFI as a system, not in isolation without the antenna lengths that typically occur in an installed system.  The noise floor from a typical contractor-installed µinverter PV system must be seen on the SA to be believed... Here, both the aviation authority and the military have issued disconnect-and-dismantle orders to several home owners that had "professionals" install systems, sadly enough a bit too close to "something important".

Twisting the cables and screening the inverters apparently has made wonders in some installs, but they remain a nuisance.

Holy shit, I live 3 minutes driving away from a small airport. Your post could have avoided some aviation problems in USA,SC

I have now the crazy idea to move all the µInv inside the house in the attic, that would make it easy to put them in a shielded box.
The radiation is coming from the long AC lines and not from the DC line from panel to the µInvs, I imagine....

Yes, that is why the micro-inverter / panel optimizer systems are much worse, because they have the Zerhacker (the amount of mayhem caused by making AC out of PV DC can't be adequately visualised if one uses nice words like "inverter" or "vibrator", so one must resort to German terms) units spread out with suitable lengths of "radiating cable" (also known as antennas) over the entire roof, without a lot of screening.. DC cabling is nice as long it is not being an antenna too, by virtue of too little input filtering.

[mnementh]

I've seen horror shows on yoobToob where they're connecting everything with exposed wirenuts and similar shit...?

If it'd only been Wagos!

No, seriously; that's not how it's done in Yorrp; there are special high-voltage watertight connectors and special double-insulated cables for chaining panels. 

   (image is clickable for wikipedia article) Micro-inverters is different, of course, but they too need connecting out to the grid, and there are special connectors for that too.

Okay... so we're more likely talking 1d10t cowboys and whack-job off-the-gridders doing this stoopit shit, or are you saying that the difference is that PV installation/deployment actually has some regulation over there, where over here it's still a wild wild west show...? 

mnem
 

[mnementh]

      Local CL has this Heath SB-301 for $90. Made me pause for a moment then dismissed it. Why? Well, it was a kit. Build quality is definitely a crap shoot.
And who knows if it ever worked properly when it was complete. That's a definite consideration. I'll pass but I did give it some thought.

I've seen worse.... much worse.

It seems to me that for many of those who collect these, a large part of the joy is dismantling completely, cleaning everything up and restoring the cabinet, then building as if it were a new kit by themselves or as a shared experience with a friend or offspring. That unit will definitely be a prime candidate for this crowd... Honestly, I find myself looking at that, remembering times spent with grand-dad and getting a little misty... 

mnem
*sigh*

[Zucca]

Yes, that is why the micro-inverter / panel optimizer systems are much worse, because they have the Zerhacker (the amount of mayhem caused by making AC out of PV DC can't be adequately visualised if one uses nice words like "inverter" or "vibrator", so one must resort to German terms) units spread out with suitable lengths of "radiating cable" (also known as antennas) over the entire roof, without a lot of screening.. DC cabling is nice as long it is not being an antenna too, by virtue of too little input filtering.

Hey let's make a Kickstartet for a device that can harverst RF energy from cables on the roof!
After preparing a nice video, in one year we could have 1M$ raised from morons!

Jokes aside, I prefer to calm down some PV DC lines rather than a spider web of AC lines after some µinv.
RF scares me, it's all vooo dooo.

[dl6lr]

ALS MENSCH ZU DOOF, ALS SCHWEIN ZU KLEINE OHREN!
(Too stupid for a human, the ears too small for a pig)

This is the only thing left for me to say about a contractor from a nordic country which shares a sizable length of border with the evil empire. When you see 7/8" transmission line brought into a shelter and then connected via a stack of an attenuator, a surge arrester and an adaptor directly to an N connector on a RF unit those people should not even be trusted to install a cast iron sewage line. Really.
Is basic mechanics like the lever advantage really beyond the grasp of such ogres?

Just checking here...  You mean NO proper securing or strain relief ... at all?

single plastic cable tie more than 50 cm away, next in 1.5m

Well, I remember a famous Microchannel RIC multiport adapter card. This one had a big connector on the back side with an extension cord to the breakout box that was as stiff, you could use as tow-bar.

[mansaxel]

Okay... so we're more likely talking 1d10t cowboys and whack-job off-the-gridders doing this stoopit shit, or are you saying that the difference is that PV installation/deployment actually has some regulation over there, where over here it's still a wild wild west show...? 

It's a bit of both, ackshually. There are hacks installing this; they're using the nice plugs and cables, but disregarding the EMI/RFI part (they've never even heard those words). 

The industry at large is only slowly waking up to the interference problem, and as I mentioned above, they usually crept around legislation by weaseltesting the components rather than the system.

[Cerebus]

..., because they have the Zerhacker (the amount of mayhem caused by making AC out of PV DC can't be adequately visualised if one uses nice words like "inverter" or "vibrator", so one must resort to German terms) units ...

No, that needs a proper twenty-seven syllable German compound noun to get the right Gestalt for it. Unheimlichwechselndegeräuscheerzeugenderaparatus or somesuch, more properly constructed, word.

[mnementh]

Yes, that is why the micro-inverter / panel optimizer systems are much worse, because they have the Zerhacker (the amount of mayhem caused by making AC out of PV DC can't be adequately visualised if one uses nice words like "inverter" or "vibrator", so one must resort to German terms) units spread out with suitable lengths of "radiating cable" (also known as antennas) over the entire roof, without a lot of screening.. DC cabling is nice as long it is not being an antenna too, by virtue of too little input filtering.

Hey let's make a Kickstartet for a device that can harverst RF energy from cables on the roof! After preparing a nice video, in one year we could have 1M$ raised from morons!

Jokes aside, I prefer to calm down some PV DC lines rather than a spider web of AC lines after some µinv. RF scares me, it's all vooo dooo.

Yeah, just remember that the DC cabling isn't the only antenna for any switching noise that escapes back up the wires; when looked at with RF in mind, the collection grid of the PV cell itself is disturbingly reminiscent of a patch antenna.

mnem
 

[Cerebus]

ALS MENSCH ZU DOOF, ALS SCHWEIN ZU KLEINE OHREN!
(Too stupid for a human, the ears too small for a pig)

This is the only thing left for me to say about a contractor from a nordic country which shares a sizable length of border with the evil empire. When you see 7/8" transmission line brought into a shelter and then connected via a stack of an attenuator, a surge arrester and an adaptor directly to an N connector on a RF unit those people should not even be trusted to install a cast iron sewage line. Really.
Is basic mechanics like the lever advantage really beyond the grasp of such ogres?

Just checking here...  You mean NO proper securing or strain relief ... at all?

single plastic cable tie more than 50 cm away, next in 1.5m

Well, I remember a famous Microchannel RIC multiport adapter card. This one had a big connector on the back side with an extension cord to the breakout box that was as stiff, you could use as tow-bar.

I lived through the days of the original 10BASE5 ethernet. The bright yellow variant on RG-8/U used to connect that up could lever heavy early workstations off desks.

[mansaxel]

..., because they have the Zerhacker (the amount of mayhem caused by making AC out of PV DC can't be adequately visualised if one uses nice words like "inverter" or "vibrator", so one must resort to German terms) units ...

No, that needs a proper twenty-seven syllable German compound noun to get the right Gestalt for it. Unheimlichwechselndegeräuscheerzeugenderaparatus or somesuch, more properly constructed, word.

That compound word needs to contain "Gerät", that's my input. "Schwergewichtsgeräuschergänzungszerhackergerät"

[TERRA Operative]

Here's a question for the radio aficionados here.

What's the go with shortwave radios? If I want a really good one (new or second hand), what should I look at for a self-contained radio (I.e. no rtl-sdr type gizmos).

[mnementh]

Here's a question for the radio aficionados here.

What's the go with shortwave radios? If I want a really good one (new or second hand), what should I look at for a self-contained radio (I.e. no rtl-sdr type gizmos).

To listen...? Probably the Grundig Satellit series; legendary selectivity and sensitivity for a tabletop/portable. To talk on...? You'll have to ally yourself with one of the major camps and do a deep dive; over here I guess that's primarily Hallicrafters, Yaesu, and Heathkit oh and collins, if you want mil-spec (thanks med).

Unless you're talking code-free license; then I suppose you may as well just get a cheap Baofeng. 

mnem
 

[Specmaster]

      Local CL has this Heath SB-301 for $90. Made me pause for a moment then dismissed it. Why? Well, it was a kit. Build quality is definitely a crap shoot.
And who knows if it ever worked properly when it was complete. That's a definite consideration. I'll pass but I did give it some thought.

I've seen worse.... much worse.

It seems to me that for many of those who collect these, a large part of the joy is dismantling completely, cleaning everything up and restoring the cabinet, then building as if it were a new kit by themselves or as a shared experience with a friend or offspring. That unit will definitely be a prime candidate for this crowd... Honestly, I find myself looking at that, remembering times spent with grand-dad and getting a little misty... 

mnem
*sigh*

Always of course assuming that you can get hold of the original build instructions, maybe there is a supplier of these out there somewhere?

[med6753]

Here's a question for the radio aficionados here.

What's the go with shortwave radios? If I want a really good one (new or second hand), what should I look at for a self-contained radio (I.e. no rtl-sdr type gizmos).

I don't think you could go wrong with any of the modern offerings from makers such as ICOM or Yaesu. But be prepared to take out a mortgage. 

But when only the best will do. Collins R-390A. 

[mansaxel]

Here's a question for the radio aficionados here.

What's the go with shortwave radios? If I want a really good one (new or second hand), what should I look at for a self-contained radio (I.e. no rtl-sdr type gizmos).

If I was to buy a listening radio today, I'd go for perhaps Icom IC-R7x, Yaesu FRG, JRC NRD-something. The Lowe receivers are nice.  All these are good machines to listen to shortwave, both CW, SSB and AM. A lot of HF non-broadcast (as in the messages having a limited recipient group, and not are intended for public consumption) traffic today is data, most often using MIL-STD 188-141A ALE or later standards, and that is something one can hear, but most likely not decode; it tends to be encrypted email/ RTTY.

[med6753]

      Local CL has this Heath SB-301 for $90. Made me pause for a moment then dismissed it. Why? Well, it was a kit. Build quality is definitely a crap shoot.
And who knows if it ever worked properly when it was complete. That's a definite consideration. I'll pass but I did give it some thought.

I've seen worse.... much worse.

It seems to me that for many of those who collect these, a large part of the joy is dismantling completely, cleaning everything up and restoring the cabinet, then building as if it were a new kit by themselves or as a shared experience with a friend or offspring. That unit will definitely be a prime candidate for this crowd... Honestly, I find myself looking at that, remembering times spent with grand-dad and getting a little misty... 

mnem
*sigh*

Always of course assuming that you can get hold of the original build instructions, maybe there is a supplier of these out there somewhere?

Assembly manual would be no problem. That would be one hell of a project to completely tear down and rebuild. But one of the biggest concerns is all those crystals. Wanna lay bets on how many are dead and damn near unobtainium? 

[TERRA Operative]

I'm just looking to listen to broadcasts from around the place etc. but I have no idea about radio stuff, its one thing I've never got into before.

Something semi-portable to portable and not toooo boat-anchory would be perfect, but when taking a look at what's around in Akihabara, my head starts to spin.... Although the Japanese brands are easy to find considering my location.

[mnementh]

Assembly manual would be no problem. That would be one hell of a project to completely tear down and rebuild. But one of the biggest concerns is all those crystals. Wanna lay bets on how many are dead and damn near unobtainium? 

The Heathkit clubs will have a source, just like the manuals. Also, I remember reading an article on OXCOs (Maybe Wolfgang...?) recently where the author found a supplier who did custom-cut crystals for ~$20 each any qty.

Again, for this crowd it is a labor of love, like restoring a classic automobile. Money is just the fuel for that joy.

mnem
 

[BU508A]

Here's a question for the radio aficionados here.

What's the go with shortwave radios? If I want a really good one (new or second hand), what should I look at for a self-contained radio (I.e. no rtl-sdr type gizmos).

One of the best ever built shortwave radio receivers was the Rohde & Schwarz EK07[1]:

ebay offer: https://www.ebay.com/itm/224813586917

The next one developed by R&S was the EK47 from 1969 (with Nixie tubes):

ebay offer: https://www.ebay.com/itm/194437279914

In 1979 followed the successor, the EK070:

no offers found for the EK070

Further details (in German):
EK07
EK47
EK070

[1]
That was a statement from my professor of high-frequency engineering.

[med6753]

I'm just looking to listen to broadcasts from around the place etc. but I have no idea about radio stuff, its one thing I've never got into before.

Something semi-portable to portable and not toooo boat-anchory would be perfect, but when taking a look at what's around in Akihabara, my head starts to spin.... Although the Japanese brands are easy to find considering my location.

What ever you decide on stay far away from this receiver. Heath was on their downward spiral when they released this piece of junk.