Elenos ETG400/1K

[ehsanspicedigital]

Hi, Hope all are well. I have an elenos ETG 400/1000. it’s died after many years in service.

A few weeks ago, lightning hit the antenna. Everything was fine somehow and the TX had survived. Now 3 days ago lightning struck again.

Prior to this there was a spike on the mains voltage which took out the processor. I had the XLR’s patched into the MPX input on the TX as a temporary fix. Keep this in mind for later..

The TX took the lightning strike overnight. The station is in Pakistan and I am working off the info our engineer there has provided me.

Everything was unplugged, as our station goes off-air daily from 01:00-06:00, as with the power and weather conditions in Pakistan it isn’t worth keeping it on air and risking a mains voltage spike. Back to the main point. The TX was off-air, lightning struck. It took out the TX, and furthermore the Soundcraft Series 10 Mixing Desk. Somehow power went through the audio route, straight into the Mixing desk. You can see the condition of the mixing desk here. It’s the same across all of the modules.

Now the TX powers on, It’s internal RF indicator shows the RF is okay, shown in this video \/


Also it’s showing audio on the MPX input when nothing at all is connected. (As soon as the self test completes it should fire up the fans, even if the RF output is muted.) Shown Below \/


I’ll show the IC that has a little hole in it. On the audio board, Cannot find this IC anywhere, This is all i can seem to find damaged, on the board.. Nothing else i can see if damaged or shorted. I have also attached a pic of the Same IC next to it. They have the same marking.

Please can someone help me find the IC and help me.

(the pics with burn marks on the PCB are from the Mixing desk. the pics of the IC’s are from the TX. )

[Albert H]

Unfortunately, a lightning strike will destroy semiconductors instantly, often without obvious signs of damage. Other components that haven't failed yet might work for a while, but will never be reliable. There is no reliable way of protecting against lightning. You can go some way towards protecting your gear with Tritium-filled Gas Discharge Tubes (difficult to find these days and really expensive, but the only component that responds quickly enough to handle lightning), but these will only work at low power, with low voltages.

Your transmitter - and everything connected to it - is destroyed. It's NOT repairable, and if you did manage to get it to work, it'll never be reliable - it will be sure to fail shortly.

If you want to get the station back on the air, you're going to have to spend a lot of money, to replace everything!

You can try to install a sacrificial earthed probe above your transmitting aerial, in an attempt to try to re-route future strikes, but this seldom works really effectively. Valved transmitters can sometimes withstand a strike, but all their associated hardware usually gets fried too.

Your only real option is to buy new gear, and try to find another location nearby that's better protected against strikes.

[ehsanspicedigital]

Id need help in getting the unit working with the help of everyone’s expertise on here, if it even only works for a little amount of time, i need a temporary fix until i can source another TX. The Soundcraft series 10 took me 3 days to fix, But it’s back up and running. There was a lot of damaged voltage regulator’s, in the TX this is all i can see that is damaged, the other shorted resistors etc can be sourced easily. Can someone please help me fix this or find an alternative.

[ehsanspicedigital]

Id need help in getting the unit working with the help of everyone’s expertise on here, if it even only works for a little amount of time, i need a temporary fix until i can source another TX. The Soundcraft series 10 took me 3 days to fix, But it’s back up and running. There was a lot of damaged voltage regulator’s, in the TX this is all i can see that is damaged, the other shorted resistors etc can be sourced easily. Can someone please help me fix this or find an alternative.

[ehsanspicedigital]

Id need help in getting the unit working with the help of everyone’s expertise on here, if it even only works for a little amount of time, i need a temporary fix until i can source another TX. The Soundcraft series 10 took me 3 days to fix, But it’s back up and running. There was a lot of damaged voltage regulator’s, in the TX this is all i can see that is damaged, the other shorted resistors etc can be sourced easily. Can someone please help me fix this or find an alternative.

[EFR]

Its LF347 quad opamp, quite basic part with its ID on top.

I have some, but letter to Pakistan seems to cost 36€ and take 2-4 week deliver. Local source might be cheaper.

Check PA-board after that hit..

[Frequent Lee]

Those cooked copper traces and that area will need the board to be lightly sanded down and the damaged traces rebuilding with kynar wires first and foremost, then when it's been tested for continuity and there's absolutely zero shorts a UV solder mask applied to seal it and protect the area from oxidation etc.

Then there will be other duff components to find that appear visually to be ok, lots won't be.

It's a BIG job that will require a decent soldering station, UV lamp, bags and bags of electrolytic caps, ceramics, resistors and ICs.

You would be better off buying a replacement or something else with the equivalent specs you're requiring for the station.

A good solution would be to have a transmitter you can use a wireless link with, then in future if the antenna is struck by lightening again it will only pop the TX and link receiver. Your studio kit and processing stuff is isolated from the transmitter by way of the WiFi link.

Have you considered using a UK or Dutch pirate rig, the good builders are knocking out 1kw London style rigs that are spectrally clean to within the permitted spec.

[mikroman]

As Albert said, there is no 100% protection against lightning strikes. From my experience so far, I advise considering several factors that mitigate the consequences. 1. good grounding of the pole, 2. antenna position (avoid the top of the pole), 3. adding a coax rf ground kit, 4. adding a cavicity filter - in addition to its basic purpose, it reduces damage 5. using grounding of the rack in which the equipment is located, 6. installing a 1:1 isolation transformer, 7. ensuring surge protection in the electrical distribution cabinet. All together it costs less than buying a new mixer and kilowatt elenos.

[ehsanspicedigital]

EFR, thanks for the information. Great big help.

Frequent Lee, I’m quite good at soldering i’d say. Over the years experience has taught me, and my Metcal SP200 has been a perfect soldering station for me so far! The wireless link suggestion is clever, Might have to think about it.

I’ve got a 1kw Dutch rig. It won’t survive on the pakistan electricity. Sometimes you’ve got 190v on the mains and sometimes 260, i’ve seen it spike up to 480v+ momentarily too. This Elenos unit has been quite tolerant to the horrible power there, That’s why I like them. I had a newer Indium version, It fried after 3 months in service. Put this unit straight back on. Been going for 14 years. With service these units are built to last.

Mikroman, You and albert both are correct.
Believe it or not, there’s no proper grounding/protective earth on the mains coming into the building. same nearly anywhere in Pakistan. I did install a Ground Rod, but because i purchased it there, it corroded and haven’t got around to replacing! Going to purchase one from here and ship it across, Can’t trust electrical there,

While i’m working on getting all of the components for this Mixing desk and TX, i’ve got a spare Yamaha desk running and a 1/2kW elenos, to air for the time being.

It’s so hard to run a station remotely, And the worst thing is sourcing components for repair in Pakistan. They’re mostly 99% of the time counterfeit and don’t last long..

I’ve also found with the lot at elenos, Since they’ve been acquired by DACTA, they have started turning a blind eye to emails about older elenos Units, i sent a email a few days after my initial email for the repair/service of the unit, no response, but when i go to contact them to purchase a new TX i’ll get a response within 1 hour lol, and then still no response for the other email.

I find that a lot with the italians. Your kit is obsolete and they don’t want anything to do with it!

Once again great thanks for the help lads!

[Albert H]

A great way of getting a good earth is to dig a large hole, and bury either one or (preferably) two galvanised dustbins with firmly connected, heavy duty stranded wire going above gound to the equipment. The dustbins will last for years - I have two buried in my garden here that I've used for about fifteen years! I bought mine at a nearby hardware store for about £11 each, and the cable I used was scrap, so cost nothing. The large surface area of the insides and outsides of the dustbins makes sure that the earth is really good!

Unfortunately, semiconductor devices can be damaged or destroyed in nanoseconds by lightning. Even induced spikes on your cabling from nearby lightning can wreak havoc. The risetime of a lightning event is so fast, that almost all protective devices don't respond fast enough to prevent damage.

One site I used to maintain went through three expensive FET-output tranmitters within two weeks. The station owners were pretty annoyed, and asked if there was any way I could keep them on the air reliably....

First step was to improve the earthing at the site (I used dustbins!), and then replace the blown transmitter - we procured a fairly ancient (1950s) RCA valved rig. The next step was to add a sacrificial earthed electrode at the top of their tower - several metres above their transmit aerials. The idea (suggested by my Father) was to "attract" lightning discharges to the earthed tower, rather than the transmit feedline!

So far, the museum-piece rig has run for 11 years without interruptions (apart from scheduled maintenance), and gives a better signal than their old, expensive FET boxes.

[mikroman]

@ehsanspicedigital something is wrong with the PM, I see you are not receiving them. I have the service manual for the etg1000, I can send it to you, if you haven't already given up on it.

[ehsanspicedigital]

mikroman, i have replied to you now! Have a look please!