Element Prices

[Jan]

I got fax with prces for element from Channel Industries.


The price for a single element


2.000" x 0.500" x 0.165" is $32.50.


We need 7 per array = $227.50


Regards. Jan


P.s. No answer about max voltage was given.

[bob]

Re: Element Prices

Jan,


Still working on prices. I found out the reason for size limits. (at least at Piezo Kinetics.) With these guys, the ceramics are made by a 100 ton press. They are capable of going up to 4 inches.


I asked, and they do have some Type III, 4 inch pieces in stock. Unfortunately, they are resonant at over 600kHz. (Darn, so close and yet so far!)


I will find out about getting some other pieces, at 500 and 250 kHz. The delivery may take a while. What about your end?


Also, has anyone called MSI yet?


-Bob

[Tod]

Re: Element Prices

Bob,


You might be able to change the resonant frequency by the backing and window thickness. The frequency has to do with the inertia of the mass. That is why when the ceramics get mounted the frequency changes. Just trying to help. You guys are just out of my range to be useful, but I’m understanding and learning a lot. Keep it up. Thanks Sture, I printed your schematics on 4 sheets, 11x17 and put them on the wall to follow along.


Tod

[Jan]

Re: Element Prices

Tod,


Well I am just learning also.


What I am afraid of is that using backing material to change frequency will "force" the element to a certain frequency.


The element will not "like" that which might result in worse echo signal levels.


Its just a hunch, I am not sure about this.


Regards, Jan

[Jan]

Re: Element Prices

Bob,


Do you have a price for the 600 kHz elements ?


I would think 500 kHz will be same price ± few dollars.


I would like to go for 500 kHz because if like the extra resolution of 500kHz more that the extra range of 250kHz.


I am mainly looking for old wooden wrecks... well, the odd U-boot will also do though..


For these wooden wrecks I will need the extra resolution.


MSI ?


Never heard of it.


I will have a look here in Holland... with al this internet stuff completely forgot our own Yellow pages..


Regards, Jan

[Charles]

Re: Element Prices

I'm curious. If the elements determine the frequency of the system, how are some sonars like JWFishers unit able to operate dual frequencies. Do they have 2 pairs of transducers? You can switch frequencies on the fly. It seems that it would be prohibitive to have 2 sets of transducers so does anyone know what is being altered to switch from 100khz to 600khz and back real time? I'm certainly not trying to complicate the project but if it weren't that difficult or expensive, a dual frequency unit like that would satisfy everyone's requirements.


Thanks,


Charles

[bob]

Re: Element Prices

Charles,


Take a look at Sture's schematic post. It looks like in fact they do use 2 sets of transducers. Maybe there are other ways, but these guys seem to have taken the simpler approach...


-Bob

[bob]

Re: Element Prices

Jan,


The dimensions are 4 inches by .25 inches by .082 inches (Mighty thin!) The material is #804. if you look on www.piezo-kinetics.com, you can see the specs.


600kHz was just a guestimate... You will need to figure out the frequency to be sure.


I was talking about IN STOCK parts. They will be more than happy to cut different sizes, but it will take time for them to make the ceramics.


At any rate, I will get a price for you!


Also, MSI is Material Systems Incorporated which is on the forum mainpage! To save everyone a click over to it, the URL is


http://www.matsysinc.com/


I wonder what their prices are like, and how big they go..


-Bob

[Jan]

Re: Element Prices

Bob,


I think in Stures post it shows the left and right side transducers.


Regards, Jan

[bob]

Re: Element Prices

Jan,


Ya gotta look closer! under the top receive section, it says '100 kHz TVG amp' and the bottom it says '500 kHz TVG amp'


Also, by 'dynamic' Sture means dynamic range (I believe) which is the ratio of your largest acceptable signal to your smallest. Because close objects will return a loud ping that will be orders of magnitude larger than the return from a distant object, you need a wide dynamic range.


So to put it simply, high bandwidth = more details, high dynamic range = longer sonar range.


-Bob