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      Pingers and Hydrophones

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      david f
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      Pingers and Hydrophones

      Post  david f on Fri Nov 12, 2010 4:20 pm

      The instructions for the very useful Loughborough unit can be found at:

      The hydrophone itself:
      http://sonar-fs.lboro.ac.uk/uag/downloads/bender2.pdf

      The preamplifier:
      http://sonar-fs.lboro.ac.uk/uag/downloads/preamp2.pdf

      The instructions are very good. The only mods I would suggest are to the preamp (see later posts) and to the hydrophone:
      - Maybe use polycarbonate rather than perspex.
      - For the cable gland, try epoxying a brass tube into the polycarbonate. Then slide the cable through this gland. Then slide a piece of silicone tubing over the cable and the brass tube.

      I will post more constructional details over in the "How to" section.


      Last edited by david forrest on Fri Dec 03, 2010 11:01 am; edited 1 time in total
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      Re: Pingers and Hydrophones

      Post  david f on Sat Nov 27, 2010 10:58 am

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      Re: Pingers and Hydrophones

      Post  david f on Sat Nov 27, 2010 10:59 am

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      Re: Pingers and Hydrophones

      Post  david f on Sat Nov 27, 2010 11:01 am



      Last edited by david forrest on Sat Nov 27, 2010 11:10 am; edited 1 time in total
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      Re: Pingers and Hydrophones

      Post  david f on Sat Nov 27, 2010 11:02 am

      Partlist exported from C:/Users/David/Desktop/Preamplifier revamp 2010/Preamp12.sch at 11/27/2010 10:49:03 AM

      Board dimensions 3.75 inches by 1.5 inches

      Part Value Device Package Description
      A1 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      A2 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      AMPINPUT LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      B1 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      B2 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      C1 0.1uF CAP-2,5 C-2,5
      C2 10uF ELC-5 ES-5
      C3 2.2nF CAP-2,5 C-2,5
      C4 470pF CAP-2,5 C-2,5
      C5 100uF ELC-5 ES-5
      C6 100uF ELC-5 ES-5
      C7 10nF CAP-2,5 C-2,5
      C8 0.1uF CAP-2,5 C-2,5
      C9 0.1uF CAP-2,5 C-2,5
      C10 100uF ELC-5 ES-5
      C11 100uF ELC-5 ES-5
      C12 10uF ELC-5 ES-5
      C13 10uF ELC-5 ES-5
      D1 IN5402 DIODE-7,5 D-7,5
      D2 IN4148 DIODE-7,5 D-7,5
      D3 IN4148 DIODE-7,5 D-7,5
      GROUND LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      HYDROINP LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      HYDROINPUT LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      IC1 TDA2822 DIL8 DIL08 Dual In Line
      IC2 TL072 DIL8 DIL08 Dual In Line
      LED LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      LEDFLAT LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      LSP1 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      LSP2 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      LSP3 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      LSP4 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      LSP5 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      PHONE1 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      PHONE2 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      PHONE3MID LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      POW+1 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      POW+2 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      R1 47k RESEU-10 R-10
      R2 47k RESEU-10 R-10
      R3 10k RESEU-10 R-10
      R4 300k RESEU-10 R-10
      R5 160k RESEU-10 R-10
      R6 15k RESEU-10 R-10
      R7 1M RESEU-10 R-10
      R8 4.7 RESUS-10 R-10
      R9 4.7 RESUS-10 R-10
      R10 47k RESEU-10 R-10
      SWIT1 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      SWIT2 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      VOL2 LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      VOL100KLOG LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555
      VOLSLIDER LSP10 LSP10 LSP10 SOLDER PAD drill 1.0 mm, distributor Buerklin, 12H555


      Last edited by david forrest on Sat Nov 27, 2010 11:11 am; edited 1 time in total
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      Re: Pingers and Hydrophones

      Post  david f on Sat Nov 27, 2010 11:04 am

      I enclose the board details and parts list for my modification of the Loughboroough Hydrophone.

      The circuit diagram above is basically the Loughborough design but I've put an audio amplifier in to drive ordinary (8 ohm) headphones.(You could use a speaker but headphones are best when you are searching for a lost submarine.)

      The circuit has also been altered to enable use of a single battery.(A 9.6v transmitter battery is a handy choice.)

      The unit has very high gain and should be fitted in a metal box. Careful use of the volume control is suggested to avoid oscillation and in a quiet pond you can hear a Pinger or drive motor noises at 20 to 30 feet, servos or the click of the Pinger unit from a few feet. (The Pinger chip transmits a "cheep" for long range detection followed by a very short "click" for short range detection.)


      (These details are published "at your own risk" and with no support. They were originally produced commercially but the soldering and support operations became too much for me! I hope these details help the wider submarine community to recover their submarines. Sadly it is not a question of "if" I lose a submarine but "when". I have now lost and recovered 3 of my submarines successfully.)
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      Re: Pingers and Hydrophones

      Post  david f on Fri Dec 03, 2010 10:27 am

      Pinger details showing the use of the handy B & Q stop end as an enclosure.

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      Re: Pingers and Hydrophones

      Post  david f on Fri Dec 03, 2010 10:36 am

      The Pinger should be placed in a free flood part of your submarine where it will provide a sound source for about a month.
      Construction details (very easy):
      Glue a PVC disk to form one end cap of the enclosure.
      Epoxy a piezo sounder to the inside of this end cap.(Solder the leads on first - a light touch needed. Keep a weight on it whilst the epoxy is setting to avoid air bubbles.)
      Solder the piezo sounder and the battery holder (2xCR2032 lithium batteries) to the Pinger chip (£5 only for AMS members. See For Sale section.)
      Use a piece of card (the red thing in the photo) to switch the unit off.

      A crude little thing that provides a lot of piece of mind!
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      Re: Pingers and Hydrophones

      Post  david f on Wed Jun 01, 2011 8:57 am

      UPDATE ON THIS - I got water in this B & Q enclosure this Sunday! (My water pump has failed also - see How to section!)

      Maybe I will go back to the original Pinger design with a sealed enclosure opened only for battery changes.(Uses a reed switch to turn on and off by a magnet.)

      Perhaps the philosophy of sealing is - "better to break seals only very occasionally!"

      (I forgot to mention that Harry B has pointed out that the Loughborough University links don't work anymore.I have copies of these articles so pm me an email address if you would like copies.)

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      Re: Pingers and Hydrophones

      Post  david f on Sat Aug 20, 2011 8:19 am

      Actually I've gone back to using these very useful B & Q caps. They are good.

      I've now also taken the precaution of epoxying a short length of brass tubing into the enclosure. This is so that I can pressure test it using my normal (orange!) inflated balloon method which I do on all my subs.
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      Cheap and Simple Hydrophone Preamplifier/Amplifier for Headphones. By David Forrest and Brian Alps.

      Post  david f on Sat Aug 20, 2011 8:30 am

      Cheap and Simple Hydrophone Preamplifier/Amplifier for Headphones. By David Forrest and Brian Alps.

      (I would normally have published this first in our magazine but I felt that it was best to put it up here for the benefit of the model submarine community. The more hydrophones the better!)

      This summer I have been having a look at making hydrophones more easily and cheaply available.

      They are very useful things for our hobby. They can pick up motor, pump and even servo noises at ranges of 10’s of feet and with a Pinger, on the sub (Pinger chip available for £5 to AMS members.) you are very unlikely to lose the submarines in even the darkest, dirtiest water. The more hydrophones there are at the pond side, the better for all of us – hence this article.

      You need a hydrophone together with a preamplifier/amplifier.

      The Loughborough University “Bender” hydrophone is an excellent design. Cheap to make and very simple for the typical model submariner to build. We know about Perspex sheets, bolts, O rings etc.

      The preamplifier and amplifier using the Loughborough University design (and my mods to it) are very effective but quite complicated to build. You need to make your own printed circuit boards etc. So I had a look at what was commercially available and my suggestion would be to use the excellent kits produced by Velleman - available from Maplins.
      The kits are:
      K1803 Universal Mono Preamplifier
      K8066 3W Mono amplifier.

      They cost about £6 each and contain a good quality circuit board, components and instructions.
      Most people who have a soldering iron could make these kits (or someone could make them for you.) and they only take a few minutes to build and can be tested individually.
      Mount them in a metal box. (I used a tin box and the shortcakes were delicious – see photos) for screening.
      Connect them together to a 6 to 12 supply – a transmitter battery works well. Use a potentiometer as a volume control as per the Velleman instructions (I used a 100k rather than the 40k suggested, because it’s what I had.)
      Use a pair of good quality headphones which work better than a loudspeaker (I use Sennheiser headphones.) These will be stereo but connect across two of the three connections them so that you get sound in both phones. (If you do this you may need to mount the jack plug socket on plastic to avoid shorting to the metal case.)
      I added an on/off toggle switch (with a guard to prevent it being knocked on ) and an LED to show power on. Plug in the Bender Hydrophone which “you made earlier” and you are away.

      I’ve tried using it in comparison with the original design. This is more sensitive because it contains passive filters, but the cheap and simple design works well and should form part of your pond side kit. It should not be too difficult to add some passive filter stages to the Velleman preamp board. Perhaps more information later.



      Chatting with Brian (The Editor) at Barrow recently, he has also tried some pre-built units from Maplins with good results and no soldering is required. Brian’s words follow:
      “With regard to my construction of the hydrophone amplifier system I have attached some photos. The types of amplifiers used from 'Maplin' were:
      German 'Kemo' Universal Preamplifier Module M040, Order Code: N69AW @ £6.99, operating voltage 9-24 vdc, input voltage 2-50 mV, output voltage 200 mV, current consumption 2 mA, dimensions 30 x 25 x 15 mm.

      German 'Kemo' Universal Amplifier Module M031N, Order Code: N64AW @ £6.99, operating voltage 4.5-12 vdc,output max 3.5 W music power, loudspeaker connection 4-16 ohms, input sensitivity >80 mV, frequency response 40-20,000 Hz, dimensions 40 x 40 x 12 mm. A 10 k ohms log. pot. should be connected between signal source and the amplifier module. Preamplifier connected between the source and the pot.

      I installed a DC charging socket for a 9.6 NiCad battery which I used to use in my Tx.
      Hydrophone design according to your instructions (So basically the Loughborough model, David’s comment.), except I used thick plastic card for the discs.

      Headphones from 'Maplin' were 'ProSound' CD type.”


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      Re: Pingers and Hydrophones

      Post  david f on Sat Mar 16, 2013 11:12 am

      I have been doing some more Pinger trials in the Barrow pond in the last few weeks.

      I have been trying to make the Pinger smaller to fit in smaller models. I have now got the size down to 25mm long by 35 mm diameter using a single piezo disk. This is based on 35mm PVC pipe (of course!)Interestingly this is very close to the original "Film Can" which our Chairman Nigel was thinking about many years ago in the original magazine article. It would be hard to find the film cans now!)

      This Pinger still contains the reed switch and the 2x CR2032 batteries which give about a month's life.

      The range was about 15m using the simple "Walker's Shortbread" hydrophone. (The pinger was in my Charlie 2 and the Barrow pond was quite quiet.)

      This range was more than adequate.(You actually don't want too much range - you need to be able to "home-in" on the model and the short, rangeing click.)

      I don't think I would recommend building the Loughborough preamp/amplifier design nowadays. It is rather too complicated for our purposes.

      I see that the K8066 Velleman 3W Mono amplifier is no longer available but any audio amplifier kit or module should be OK here.

      David
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      Re: Pingers and Hydrophones

      Post  david f on Tue Mar 19, 2013 12:01 pm

      I've had some enquiries recently about the basic way of using these units. (Memories fade even on the Web!)

      You put the Pinger bit in the freeflooding area of your submarine where it it transmits a sound pulse into the water every few seconds for about a month (with the stated batteries). (It also transmits a short click which has short range of a few metres.)

      You search for the sub with a hydrophone (see the Loughborough unit

      http://www.lukemiller.org/journal/journal_pics/hydrophone/piezo_hydrophone_1995.pdf

      This plugs into an preamplifier/amplifier unit (I suggest the Velleman units as being easy to build and buy.)

      You listen through headphones (better than speakers) (See the Sennheiser ones etc.)

      Depending on the depth of the pond you are wearing waders or in a boat. (If it is deep you are going to need a diver - but at least they will know where to look.)

      You WILL get your submarine back! (Many already have. I have used it successfully 3 times so far.)
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      Re: Pingers and Hydrophones

      Post  david f on Mon Mar 25, 2013 10:10 am

      Just to say that I have tested at Barrow an alternative to the audio amp which is no longer available. This is the MAP439 1 Watt audio amplifier kit available from Maplin or www.mutr.co.uk.

      This is only 1 Watt ouput but is fine with headphones. Use it in conjunction with the Velleman K1803 Universal Mono Preamplifier and the Loughborough University hydrophone (working link above.)

      David
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      Re: Pingers and Hydrophones

      Post  profesorul on Sat Mar 30, 2013 8:17 pm

      HI DAVID,

      What do you think about these amplifier?...I have the components already and next week I wheel make some experiments with it,
      http://www.youtube.com/watch?v=VxoK-yv0Zp4
      Is the most simple and cheap I've found and it seems to work great!.
      Can You add that schematic for PINGER itself and components list?,
      The IC cip requires a programing?,
      I tray-ed 100 times to get into those link you've posted but NOT working !!!.

      THANK YOU
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      Re: Pingers and Hydrophones

      Post  david f on Tue Apr 02, 2013 9:16 am

      Hi Marius,

      That simple amplifier looks very promising. Simple but has a preamp stage. Let us know how well it works.

      The original Loughborough University links don't work any more but this is the only one you need (for the hydrophone):

      http://www.lukemiller.org/journal/journal_pics/hydrophone/piezo_hydrophone_1995.pdf

      Let me know if this link does not work.

      David
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      Re: Pingers and Hydrophones

      Post  profesorul on Wed Apr 03, 2013 8:01 pm

      Hi,

      - I didn't find all the components yet but I wheel keep you on post it.
      - I found a small piezo ceramic speaker into an old toy,and I need to find the materials to do that Hydrophone,
      - that link is working,
      - what PIC can replace yours 08M2 (in my country NOBODY bring these PIC!).....the 16F84A is working?,or what other Microcontroler can be used?.....can You send the code for programing by eMail?....what is actualy the sound produce by Your device?.

      MARIUS
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      Re: Pingers and Hydrophones

      Post  david f on Thu Apr 04, 2013 10:09 am

      The simple piezo element will work well.

      The design you showed me is for an electret microphone. It should work with a piezo input. (I think a resistor could be removed that provides a voltage to the electret.) But try the original circuit first.

      The pic and its programmed software are available for £6 for AMS members only to purchase. (Hardly a fortune! I have granted the proceeds of the sale of the pic and software to the AMS and our charity the RNLI so I can't offer source code.)

      I can probably send you a recording of a PIC signal if you would like?

      David
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      Re: Pingers and Hydrophones

      Post  profesorul on Sun Apr 07, 2013 5:43 pm

      HI DAVID,

      I understand the complexity of the problem.

      Only yesterday I succeeded to find all the components for the device.Maybe next week I can find some spare time to do it.
      From what I understand there are 2 devices:
      - a)the sound emitter - witch is made by You and mounted in the sub,
      - b)the Hydrophone - witch form Your experience - all of as should have it at home!.

      PLEASE if You can send me the sound by email.
      I'll send You by PM my mail address.

      Regards MARIUS
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      Re: Pingers and Hydrophones

      Post  david f on Mon Apr 08, 2013 10:31 am

      Hi Marius,

      That is right. You need a long lasting sound source on the submarines. (Drive batteries go flat within hours.)

      I will send the Pinger sounds recorded at Barrow to Richard to see if he can upload them here.

      David
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      Re: Pingers and Hydrophones

      Post  profesorul on Mon Apr 08, 2013 6:20 pm

      OK,
      THANK YOU

      MARIUS
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      Re: Pingers and Hydrophones

      Post  profesorul on Fri Apr 19, 2013 3:24 pm

      HI @david,

      I have a couple questions regarding these Hydrophone:

      - witch should be THE MAXIM difference between Piezo Diameter and O-ring diameter?...I have a 27mm diameter piezo and a 45mm interior diameter for the O-ring with 5mm thickness of the O-ring...it wheel be OK?;
      - I found only 3mm thick Plexiglas , can I use it?...or can I reinforce the Plexiglas by DOUBLE the sheets - to use 2 piece of 3mm glued togeder for each side to make it 6mm?....what adhesive can be used?,
      - is necesary to use ONLY the COAXIAL cable from Hydrophone to Amplyfier or I can use any good water proof cable?,
      - what should be the maximum length of the cable?

      That's wheel be all for know!.

      THANK YOU

      REGARDS MARIUS
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      Re: Pingers and Hydrophones

      Post  david f on Sat Apr 20, 2013 9:15 am

      Hi Marius,

      I don't think a Loughborough University "bender" hydrophone is very fussy as far as materials are concerned. It works like a drum and so will have a resonant frequency but what you have described will probably be OK.

      Coaxial is better to eliminate main hum etc. but there is not much mains hum by the side of a pond! Twisted cables may be well be OK.


      David
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      Re: Pingers and Hydrophones

      Post  david f on Mon Apr 07, 2014 11:08 am

      Hi All,

      The news items about the loss of the MH 370 airliner prompts me to remind model submariners about are very own Pinger beacon, to locate lost subs.

      Lots of information on the Forum and you can still buy the AMS Pinger chip for £6.

      I don't seem to hear the cheery Pinger "chirp" very much on other peoples subs nowadays so they are risking just going home with their transmitter. Unless they are lucky enough to only operate in gin-clear water which must limit their hobby rather.

      As the experts say it is not IF you lose your sub but WHEN!

      Just a gentle reminder warning for the start of the season.

      David
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      John Wrennall
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      Re: Pingers and Hydrophones

      Post  John Wrennall on Sat Mar 21, 2015 8:38 pm

      Hi David.

      I have an old Walkman tape cassette unit which is now redundant and was thinking of using it as a
      Pinger receiver by simply removing the playback head and soldering in the transducer head cable.

      Its nice and compact but have you any thoughts as to its electrical suitability?

      cheers

      John


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