PowerBox and Opto-Isolators.
 

Anyone using Powerbox AND Opto-Isolators?

I can`t find any suitable for moore than 4,8 V supply (not the stabilized 5,95 V from the Powerbox), wich in my oppinion can`t be used together with modules ment for 4,8 V only...

Any hint or URL adresss is appreciated!

Gudmund

RE: PowerBox and Opto-Isolators.
 

Hi,
Try SM Services here in the UK, Terry there is very helpful and should be able to confirm their 8 channel Opto is what you are seeking, their web site is www.smservices.net the opto is in the products/large model section I have used a number of them now without problems and the signal translation is very good when checked on a scope, btw am not sure why you wish to use an opto with the powerbox, I understood(?) that it had built in signal blocking. Mike

RE: PowerBox and Opto-Isolators.
 

Hi.

I`m aware of the S.M. module, but the spec says 4,8 V only, wich isn`t compatible with the 5,95 Volts from the PowerBox..(I think)

Alan Cardash tipped us in the Boomerang XL thread resently about the S.M. That`s how I know about it.
Btw, neat installation, Alan!

I`ve asked Terry about it, but no reply yet.
Looks like the Powerbox is missing something here?...[:-]
How about expanding it to include opto-isolation too...?

This would be the ultimate step into the issue of safety..

But until he replys, it would be very interesting to hear about anyone using a opto-isolator along with a PowerBox, and where to get one for 35 Mhz..

I mean, spending several moths salary into a model, and just use the RX for safety, doesn`t make sence too me..

Spread spectrum, the key for the future...


Gudmund

RE: PowerBox and Opto-Isolators.
 

Gudmund, why do you need opto osolators as there is de-coupling and signal amplification built into the Powerbox and using one in my FC Mig 29 the range is amazing and totally unaffected by running engines and hydraulic ECU and pump. A new programmable Power box has just arrived for my Hawk, looks a VERY nice unit.

Regards, David Gladwin.

RE: PowerBox and Opto-Isolators.
 

Hi David.

Why do we need opto-isolators......

Good question, but after the GREAT ball of fire I saw a few week ago with my Gripen, I want to aim for the paramount of safety. (! ! A awsome scene..([&o] [>:])

I tell you all, this was not a bedside story for my children.... Not at all.

As I understand you David, I don`t have to worry under any circumstances, after installing the PowerBox. Correct?

I now have 2 x 3200 Kokam on RX through the PowerBox, and this is surely a improovement. After all..

BUT, I want to reduce the factors to a minimum, wich a opto-isolator would do, in addition to the P.Box..

In some countries, they say PCM is the best, another can report PPM is the max..

Example: Norway is best on PCM, Denmark is PPM, Germany is the best at PCM again..
We must take the experiences amind, and bring them futher on.

I know MPX claim their 12 Ch IPD receiver to reconize a 2 MV signal..
This doesn`t matter at all if the signal is (and other signals as well) , are twisted to a recognizable frequency, due to mountains, walleys + +.

I just don`t wan t too cause a incident/accident, due to the set-up in my models.

Norway is the leader in sophisticated equipment for personal use in the world.... We have the world record for the number of cell phones per citicent, the record for link-antennas, almost on every hill you can see.
The mountains here Nort West can make interference, unrecognizable to the keenest on this subject.
Glad the mongest of the Jet Jockeys her in Norway are at the flatlands. ( Fagernes Air Show is at a none subject);)

If I were you David, I`d think at least twice to make a lift-off on the site where my Gripen went down, with your splended AD Hawk.. Ten years since I had a severe interference issue here, and this was with a AM from Simprop..


Brg
Gudmund

PS: The idea about a opto-isolator on a Power Box, is a best buy for me.. How about you..?

RE: PowerBox and Opto-Isolators.
 

I have received information from Emmereich at Powerbox.de, wich confirms Davids statement.

Opto-Isolators are NOT nessacery if you use the PowerBox. The interference block is enought with the PowerBox itselves..

Gudmund

RE: PowerBox and Opto-Isolators.
 

Gudmund,

That is what I thought having looked closely at the Powerbox spec for an RCJI review but I am no expert on these matters so I was interested to know why you thought they were neccessary. I was certainly NOT critical of your intentions there, if thats how I came across.

My experience with the Mig 29 seems to bear out what Powerbox claims, it has extraordinary ground (and air too I presume) range and I feel comfortable I have the best possible equipment on board, and I am using the same on my Hawk. I had been planning to use fiber optic signalling to the tail servos on the Mig (even bought the units) until the Powerbox system came along.

I also heartily endorse your belief that we need a MUCH more reliable RF link for these expensive models. Lets hope such a system arrives sooner rather than later.

Regards, David Gladwin.

RE: PowerBox and Opto-Isolators.
 

Hopefully, the leading manufacturers are very busy these days..
Anyone heard a rumour about it?

We truely deserve a idiot-proof system soon!

Of course, the prize tag would be rather high..
The first suitable system, will decide wich level this will be.

RE: PowerBox and Opto-Isolators.
 

We can install as many redundant devices as we like HOWEVER: -

Only 1 transmitter!
Only 1 servo or servo set per control surface!

Thats my 2c worth

RE: PowerBox and Opto-Isolators.
 

I have invented a truly interference free system. It also uses special circuits to detect the voltage in the servo cables and will amplify this to keep it constant 4.8 volts. It also ensures no possible problem with someone using the same frequency, as there is no way this can happen.

My only problem is finding a way to reel out the cable that attaches to the model from the control unit...........:D:D[:@]

Our problem is that there are so many frequencies and transmission methods being employed, that because we are such a small user, we will be totally at the mercy of the manufacturers who wishing to stay in business, will plump for control systems for the mass market. Unless some government directive removes us from where we are, I do think it will be a long long time before we make a leap into different technologies with much greater safety.

Do I understand correctly that because of its cleverness,the Powerbox can actually enhance the range at which quality signal can be captured? How does it do that? Or did that refer to the signal integrity from reciept to servo?

There appears to be a bit more to these PB designs, maybe should run a seperate thread on them....

Gazzer

RE: PowerBox and Opto-Isolators.
 

Today, yes..

But a long while ago, they thought the earth was flat too...

15 years ago, no one had the wildest dream of what to come.
I`ll be really surprised if a similar evolution is stucked because of todays limitations, or dead ends..

The competition among the top manufacturers today, is very tuff. To be #1 here, will mean everything to them.

How many of todays competition pilots will buy a spread-spectrum radio, fully capable of handling their jets?
I think, after a while, -all of them.. Me included, together with a huge bunch of other not competing pilots.

Our jets is simply to valuable not to do so, plus the most important issue: avoiding personal injury.

RE: PowerBox and Opto-Isolators.
 

Guys

I've been using PowerBox systems for around three years now, I started selling them two and a half years ago and so far my seven models haven't missed a beat.
Sales account for another 50+ units they again have been 100% according to customers reaction and re orders.
If you look at the manufacturing of PB equipment, its fantastic quality.

The advantage is that the servos are decoupled from the Rx-no interferance from long leads.
The signal is boosted, this helps control feel and effective range as the servos don't get into stepping as early as they would without the boost.
Voltage output at 5.9v is perfect for JR or Futaba servos (JR quote no 6v packs-5cell as they are a lot more than 6v when fully charged)
The two batteries offer back up and going for Competition or Evolution versions have fail safe switches so that they fail to on...switch on and you can remove the switches!

This is as good as it gets so far...

Regards

Dave Wilshere

RE: PowerBox and Opto-Isolators.
 

Dave,

I thought I read something a while back at the criticality of operating digital servos at the 4.8 volts. Yet again I may be wrong but knowing your fleet from afar, I guess you use a lot of digitals!!! So I would expect that an operating voltage of 5.9 volts would be just perfect for JR digitals?

Sorry to be stupid, but I have found so much information on this forum, that I can remember bits of other posts, and then lose the context of it!!!!!

There's a tad more to this than meets the eye!

Gazzer

RE: PowerBox and Opto-Isolators.
 

I use the DPSI unit from Emcotec on all my large planes.
www.emcotec.de
This acts as a dual power power supply and opto isolator

No problems with these to date,
Brian Hewson
Dublin
Ireland

RE: PowerBox and Opto-Isolators.
 

Interesting topic for me..

One thing is for sure.. Can`t wait to perform a range test, with and without my new device.
Also with and without engine running. Not that I don`t believe it`s a improovement, but to have a scale to the benefits / performance.
Stabilized voltage is a huge step in the right direction. Signal amplifying and interference protection, yes please!

I`m open to everything that improoves safety in jets, and surely mean this a important thing to focus on.

Few things are moore scary than a jet following it`s own will..

I was`nt aware of the stated interference protection of the Powerbox, this beeing just as good as a Opto-Isolator. That`s why I thougt adding a Opto-Isolator to it would lift the safety level further moore.

RE: PowerBox and Opto-Isolators.
 

Gazzer

No!

A 4 cell pack at 4.8v is...just about flat!

Off charge around 6.1v is normal and after settling 5.7v.
Under load voltage does not want to drop much below 5.0v, so between 5 and 6 volts is fine for all JR digital servos, which as you rightly say fill 99% of my Jets, large scale and helicopters.

I use Graupner 4.8v (4 cell packs) 3300 or 3600 NiMH on some PB installations like my EuroSport twin and Lightning. Good quality 4 cell packs are fine-avoid budget cells...even brand named versions, if they are cheap then thats exactly what they are...
If you want top speed and performance through the PB units use 5 cell packs or PB's excellent Li-Po packs as this is the only way you will get the regulated 5.9v output-I use the 4 cells as none of the quality battery people I deal with offer 5 cell packs.
I'm ready to try the PB Li-Po packs in one of my next projects.

Regards

Dave Wilshere
Modellbau Deutsch, Graupner, JetCat, Airworld, BVM, Ultra Precision and other quality brands!

RE: PowerBox and Opto-Isolators.
 

PBs lipo packs are not the only way to get 5.9 volts, Duralite cells also work perfectly, use them in all my jets, with regulators or Powerbox. Lipos have serious safety issues, too, particularly on jets and they can react violently if a water fire extinguisher is used on them in the event of a crash. There are also some excellent 5 cell Nicads available from Horizon Hobbies in the US known as JR Extra packs, top quality Sanyo cells, I have used them a lot with 100% satisfaction. I use them with a regulator, either the Duralite which is set at 5.6 volts or the Mini Hobby unit set, I believe. at 5.5 volts, this latter unit having dual channels so if one fails the other will still feed the receiver. But from now on no large jet of mine will fly without a Powerbox having seen how it handles the 20 servos and hydraulic pump and ECU in the Mig 29.

Regards,

David Gladwin.

RE: PowerBox and Opto-Isolators.
 

I just wonder if someone can explain me something here..

Amplifying a signal will nessacerily make a imperfection to it, as all amplifiers I`m aware of does.
Never heard of a device wich boosts a signal without making a small amount of imperfection to it..
Stronger yes, but not as clean as before.

And as the range increases, the original signal will nessacerily be weaker.
How come is this amplified signal a better guide for the servo, than the original, when we add a imperfection to it?
Is it because of it`s reached base width (like compared to a signal on a frequency scanner), wich still is in a acceptable shape?

Would have been fun to see on a ozziloscope..

I`m only asking to learn about it, whats why I`m asking the way I do.

Underlining, my oppinion is just that, and based on couriosity alone. None of my "souspicious" questions are related to place any manufacturer where they won`t find themselves comfortable.. (!)