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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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Help Question: Electronic stethoscope danger
Hello...a quick question looking for a good suggestion/solution/answer,
1) I have a small rural nursing school; 2) I have a $500 electronic stethoscope (micro-battery powered) that can hear/play/record sounds using an I-Pod by using a direct wire/plug into the I-Pod external microphone jack; 3) I-Pod sounds are very weak and you have to be within inches to hear the sound during playback; 4) I need a room full of 10 students to hear the sounds from the stethoscope; 5) I connected it to a wall-plug store-bought powered I-Pod speaker sound system and it worked great...everybody in room could hear the sounds fine!; 6) Was then informed it could possibly be a major shock hazard (110 power from wall through speakers to stethoscope to person wearing (ear pieces) and to patient's chest (diaphragm); 7) So...now I'm back to Step 1 & 2... Any suggestions on how I could truly prevent a surge danger for under $100 bucks so that I can safely use the stethoscope and the powered speaker system? Would an automotive quick-jump power pack with 110 inverter work or would the danger still be present? Is there really even a danger in the first place? Thank you very much for your wisdom, advice and expertise! William in Colorado |
#2
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Help Question: Electronic stethoscope danger
On Sat, 6 Sep 2008 05:59:07 -0600, "WJW" wrote:
Hello...a quick question looking for a good suggestion/solution/answer, 1) I have a small rural nursing school; 2) I have a $500 electronic stethoscope (micro-battery powered) that can hear/play/record sounds using an I-Pod by using a direct wire/plug into the I-Pod external microphone jack; 3) I-Pod sounds are very weak and you have to be within inches to hear the sound during playback; 4) I need a room full of 10 students to hear the sounds from the stethoscope; 5) I connected it to a wall-plug store-bought powered I-Pod speaker sound system and it worked great...everybody in room could hear the sounds fine!; OK, that's a solution. But don't most of those systems also have a battery option? 6) Was then informed it could possibly be a major shock hazard (110 power from wall through speakers to stethoscope to person wearing (ear pieces) and to patient's chest (diaphragm); Most hospitals have a staff who are trained to test and evaluate these types of devices. I assume these use a wall-wart, right? Does the wall-wart have a *real* UL label? (not a fake one!) 7) So...now I'm back to Step 1 & 2... Any suggestions on how I could truly prevent a surge danger for under $100 bucks so that I can safely use the stethoscope and the powered speaker system? Would an automotive quick-jump power pack with 110 inverter work or would the danger still be present? Don't do this... Trust me, don't even go there. There are so many better ways that will work well, that this is not practical in any way or shape. Is there really even a danger in the first place? Possibly, especially if you are using stuff from teh likes of WallyWorld... Thank you very much for your wisdom, advice and expertise! Find battery powered speakers. There are thousands of examples, and you should have no problems finding them. William in Colorado |
#3
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Help Question: Electronic stethoscope danger
On Sat, 6 Sep 2008 05:59:07 -0600, "WJW" wrote:
Any suggestions on how I could truly prevent a surge danger for under $100 bucks so that I can safely use the stethoscope and the powered speaker system? Don't use the wired speakers. You're correct that they may constitute a shock hazard. There are various wireless adapters for the iPod. http://www.griffintechnology.com/products/itripdock http://www.griffintechnology.com/category/fmtransmitters The iPod transmits the audio to a common FM receiver. The wireless provides the necessary isolation. Note that the various models are specific to whichever model iPod you're using. It appears that the transmitter covers up the microphone hole, so you may need to play with some adapters. Worst case, you can use the iPod as a recorder with the microphone attached, and then plug in the FM transmitter when playing back the recording. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#4
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Help Question: Electronic stethoscope danger
In actuality...all the I-Pod does is play/record sound (and not very well due to
the frequency/tones of heartbeat & pulse)...so...the digital stethoscope is self amplified and could operate without the I-Pod if I had a battery powered stand alone speaker system I could plug into directly with the scope...or as you suggested (great idea), a wireless transmitter that could then relay the signal to a good powerful receiver. Any suggestions (brand/model) along either line? Thanks again for this assistance! William "Jeff Liebermann" wrote in message ... On Sat, 6 Sep 2008 05:59:07 -0600, "WJW" wrote: Any suggestions on how I could truly prevent a surge danger for under $100 bucks so that I can safely use the stethoscope and the powered speaker system? Don't use the wired speakers. You're correct that they may constitute a shock hazard. There are various wireless adapters for the iPod. http://www.griffintechnology.com/products/itripdock http://www.griffintechnology.com/category/fmtransmitters The iPod transmits the audio to a common FM receiver. The wireless provides the necessary isolation. Note that the various models are specific to whichever model iPod you're using. It appears that the transmitter covers up the microphone hole, so you may need to play with some adapters. Worst case, you can use the iPod as a recorder with the microphone attached, and then plug in the FM transmitter when playing back the recording. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#5
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Help Question: Electronic stethoscope danger
On Sat, 6 Sep 2008 11:09:04 -0600, "WJW" wrote:
In actuality...all the I-Pod does is play/record sound (and not very well due to the frequency/tones of heartbeat & pulse)...so...the digital stethoscope is self amplified and could operate without the I-Pod if I had a battery powered stand alone speaker system I could plug into directly with the scope...or as you suggested (great idea), a wireless transmitter that could then relay the signal to a good powerful receiver. Any suggestions (brand/model) along either line? Nothing specific. Google for "battery powered speaker". Lots of hits. I would be tempted to suggest a battery power boom box or karaoke box. What I'm worried about it that someone is going to run it with the stethescope while charging the internal batteries. Too big a risk, so we're back to wireless again. Look at the wireless microphones available for persentations. They're usually in the commercial sound business sites. While most have a built in microphone, there are a few that allow external mics. They're unfortunately kinda pricy. You might do better with wireless speakers that are made to run off a hi-fi. You didn't supply any interface specifications, but if the stethescope puts out home hi-fi line levels (about 0dBm), one of these should work. I gotta run, but I'll see if I can find something later today. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#6
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Help Question: Electronic stethoscope danger
On Sat, 6 Sep 2008 05:59:07 -0600, "WJW" wrote:
:Hello...a quick question looking for a good suggestion/solution/answer, : :1) I have a small rural nursing school; :2) I have a $500 electronic stethoscope (micro-battery powered) that can :hear/play/record sounds using an I-Pod by using a direct wire/plug into the :I-Pod external microphone jack; :3) I-Pod sounds are very weak and you have to be within inches to hear the sound :during playback; :4) I need a room full of 10 students to hear the sounds from the stethoscope; :5) I connected it to a wall-plug store-bought powered I-Pod speaker sound system :and it worked great...everybody in room could hear the sounds fine!; :6) Was then informed it could possibly be a major shock hazard (110 power from :wall through speakers to stethoscope to person wearing (ear pieces) and to atient's chest (diaphragm); :7) So...now I'm back to Step 1 & 2... : :Any suggestions on how I could truly prevent a surge danger for under $100 bucks :so that I can safely use the stethoscope and the powered speaker system? :Would an automotive quick-jump power pack with 110 inverter work or would the :danger still be present? Is there really even a danger in the first place? : :Thank you very much for your wisdom, advice and expertise! : :William in Colorado You could buy a medical grade 120V/120V isolation transformer to power your speakers from but that will still be fairly expensive but you will probably have to sort out the socket outlet for the plug-pack. You would still have the problem that somebody could unwittingly operate the system without using the transformer. Not a problem if you are the only one looking after and using the equipment. Ideally, you need equipment suitable for a teaching environment. eg. http://www.stethoscope.com/index.cfm...&ProductID=132 If the cost seems high then you will at least be supremely confident that nobody will have their safety threatened, and that can save a lot of worry about lawsuits. |
#7
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Help Question: Electronic stethoscope danger
On Sun, 07 Sep 2008 02:00:19 GMT, Ross Herbert wrote:
: :You could buy a medical grade 120V/120V isolation transformer to power your :speakers from but that will still be fairly expensive but you will probably have to sort out the socket outlet for the plug-pack. Some transformers come complete with enclosure - ready to go. http://www.isobox.com/ |
#8
Posted to sci.electronics.repair
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Help Question: Electronic stethoscope danger
WJW wrote:
Hello...a quick question looking for a good suggestion/solution/answer, 1) I have a small rural nursing school; 2) I have a $500 electronic stethoscope (micro-battery powered) that can hear/play/record sounds using an I-Pod by using a direct wire/plug into the I-Pod external microphone jack; 3) I-Pod sounds are very weak and you have to be within inches to hear the sound during playback; 4) I need a room full of 10 students to hear the sounds from the stethoscope; 5) I connected it to a wall-plug store-bought powered I-Pod speaker sound system and it worked great...everybody in room could hear the sounds fine!; 6) Was then informed it could possibly be a major shock hazard (110 power from wall through speakers to stethoscope to person wearing (ear pieces) and to patient's chest (diaphragm); 7) So...now I'm back to Step 1 & 2... Any suggestions on how I could truly prevent a surge danger for under $100 bucks so that I can safely use the stethoscope and the powered speaker system? Would an automotive quick-jump power pack with 110 inverter work or would the danger still be present? Is there really even a danger in the first place? Thank you very much for your wisdom, advice and expertise! William in Colorado Just isolate the patient electro-mechanically from the stethoscope by placing the probe in a Plastic Baggie. The probe is most likely Plastic or Bakelite with a plastic or rubber hose anyway, A thin layer of plastic sheeting will not affect the acoustics ! Yukio YANO |
#9
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Help Question: Electronic stethoscope danger
On Sun, 07 Sep 2008 04:09:24 GMT, Yukio YANO wrote:
WJW wrote: Hello...a quick question looking for a good suggestion/solution/answer, 1) I have a small rural nursing school; 2) I have a $500 electronic stethoscope (micro-battery powered) that can hear/play/record sounds using an I-Pod by using a direct wire/plug into the I-Pod external microphone jack; 3) I-Pod sounds are very weak and you have to be within inches to hear the sound during playback; 4) I need a room full of 10 students to hear the sounds from the stethoscope; 5) I connected it to a wall-plug store-bought powered I-Pod speaker sound system and it worked great...everybody in room could hear the sounds fine!; 6) Was then informed it could possibly be a major shock hazard (110 power from wall through speakers to stethoscope to person wearing (ear pieces) and to patient's chest (diaphragm); 7) So...now I'm back to Step 1 & 2... Any suggestions on how I could truly prevent a surge danger for under $100 bucks so that I can safely use the stethoscope and the powered speaker system? Would an automotive quick-jump power pack with 110 inverter work or would the danger still be present? Is there really even a danger in the first place? Thank you very much for your wisdom, advice and expertise! William in Colorado Just isolate the patient electro-mechanically from the stethoscope by placing the probe in a Plastic Baggie. The probe is most likely Plastic or Bakelite with a plastic or rubber hose anyway, A thin layer of plastic sheeting will not affect the acoustics ! Yukio YANO Let's say you were the patient... Would you wnat your life to depend on a plastic baggie? I don't think so. The correct solutions (either battery operated, or proper medical device) has been given. |
#10
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Help Question: Electronic stethoscope danger
PeterD wrote:
On Sun, 07 Sep 2008 04:09:24 GMT, Yukio YANO wrote: WJW wrote: Hello...a quick question looking for a good suggestion/solution/answer, 1) I have a small rural nursing school; 2) I have a $500 electronic stethoscope (micro-battery powered) that can hear/play/record sounds using an I-Pod by using a direct wire/plug into the I-Pod external microphone jack; 3) I-Pod sounds are very weak and you have to be within inches to hear the sound during playback; 4) I need a room full of 10 students to hear the sounds from the stethoscope; 5) I connected it to a wall-plug store-bought powered I-Pod speaker sound system and it worked great...everybody in room could hear the sounds fine!; 6) Was then informed it could possibly be a major shock hazard (110 power from wall through speakers to stethoscope to person wearing (ear pieces) and to patient's chest (diaphragm); 7) So...now I'm back to Step 1 & 2... Any suggestions on how I could truly prevent a surge danger for under $100 bucks so that I can safely use the stethoscope and the powered speaker system? Would an automotive quick-jump power pack with 110 inverter work or would the danger still be present? Is there really even a danger in the first place? Thank you very much for your wisdom, advice and expertise! William in Colorado Just isolate the patient electro-mechanically from the stethoscope by placing the probe in a Plastic Baggie. The probe is most likely Plastic or Bakelite with a plastic or rubber hose anyway, A thin layer of plastic sheeting will not affect the acoustics ! Yukio YANO Let's say you were the patient... Would you wnat your life to depend on a plastic baggie? I don't think so. The correct solutions (either battery operated, or proper medical device) has been given. Surgeons have been doing this for generations, only they call them surgical gloves ! Standard, "conventional" stethoscopes were always electrically isolated from the probe tip by rubber tubing . If it was in the middle of a epidemic I would insist that a NEW baggie be placed on the Probe Tip . Where are you going to find and afford this Medical device ! Yukio YANO |
#11
Posted to sci.electronics.repair
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Help Question: Electronic stethoscope danger
Jeff Liebermann wrote:
On Sat, 6 Sep 2008 11:09:04 -0600, "WJW" wrote: In actuality...all the I-Pod does is play/record sound (and not very well due to the frequency/tones of heartbeat & pulse)...so...the digital stethoscope is self amplified and could operate without the I-Pod if I had a battery powered stand alone speaker system I could plug into directly with the scope...or as you suggested (great idea), a wireless transmitter that could then relay the signal to a good powerful receiver. Any suggestions (brand/model) along either line? Nothing specific. Google for "battery powered speaker". Lots of hits. I would be tempted to suggest a battery power boom box or karaoke box. What I'm worried about it that someone is going to run it with the stethescope while charging the internal batteries. Too big a risk, so we're back to wireless again. Look at the wireless microphones available for persentations. They're usually in the commercial sound business sites. While most have a built in microphone, there are a few that allow external mics. They're unfortunately kinda pricy. You might do better with wireless speakers that are made to run off a hi-fi. You didn't supply any interface specifications, but if the stethescope puts out home hi-fi line levels (about 0dBm), one of these should work. I gotta run, but I'll see if I can find something later today. This would hopefully suit you, they are available in Walmart and work quite well, I had one on my mp3 player in my car for ages due to my CD player being bust. All you need is your radio boombox tuned to the transmit signal. http://catalog.belkin.com/IWCatProdu...duct_Id=166903 |
#12
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Help Question: Electronic stethoscope danger
Archon...Good idea but I can not tell if the Belkin requires the cigarette plug
or can it operate independently with internal batteries? William "Archon" wrote in message ... Jeff Liebermann wrote: On Sat, 6 Sep 2008 11:09:04 -0600, "WJW" wrote: In actuality...all the I-Pod does is play/record sound (and not very well due to the frequency/tones of heartbeat & pulse)...so...the digital stethoscope is self amplified and could operate without the I-Pod if I had a battery powered stand alone speaker system I could plug into directly with the scope...or as you suggested (great idea), a wireless transmitter that could then relay the signal to a good powerful receiver. Any suggestions (brand/model) along either line? Nothing specific. Google for "battery powered speaker". Lots of hits. I would be tempted to suggest a battery power boom box or karaoke box. What I'm worried about it that someone is going to run it with the stethescope while charging the internal batteries. Too big a risk, so we're back to wireless again. Look at the wireless microphones available for persentations. They're usually in the commercial sound business sites. While most have a built in microphone, there are a few that allow external mics. They're unfortunately kinda pricy. You might do better with wireless speakers that are made to run off a hi-fi. You didn't supply any interface specifications, but if the stethescope puts out home hi-fi line levels (about 0dBm), one of these should work. I gotta run, but I'll see if I can find something later today. This would hopefully suit you, they are available in Walmart and work quite well, I had one on my mp3 player in my car for ages due to my CD player being bust. All you need is your radio boombox tuned to the transmit signal. http://catalog.belkin.com/IWCatProdu...duct_Id=166903 |
#13
Posted to sci.electronics.repair
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Help Question: Electronic stethoscope danger
Ross...good idea but not an option because we want the sound heard by
all...approximately 15 people at a time. We already have and use dual & triple stethoscopes but they mean the task has to be repeated over and over whereas if we could just broadcast for all to hear at once...presto! William "Ross Herbert" wrote in message ... On Sat, 6 Sep 2008 05:59:07 -0600, "WJW" wrote: :Hello...a quick question looking for a good suggestion/solution/answer, : :1) I have a small rural nursing school; :2) I have a $500 electronic stethoscope (micro-battery powered) that can :hear/play/record sounds using an I-Pod by using a direct wire/plug into the :I-Pod external microphone jack; :3) I-Pod sounds are very weak and you have to be within inches to hear the sound :during playback; :4) I need a room full of 10 students to hear the sounds from the stethoscope; :5) I connected it to a wall-plug store-bought powered I-Pod speaker sound system :and it worked great...everybody in room could hear the sounds fine!; :6) Was then informed it could possibly be a major shock hazard (110 power from :wall through speakers to stethoscope to person wearing (ear pieces) and to atient's chest (diaphragm); :7) So...now I'm back to Step 1 & 2... : :Any suggestions on how I could truly prevent a surge danger for under $100 bucks :so that I can safely use the stethoscope and the powered speaker system? :Would an automotive quick-jump power pack with 110 inverter work or would the :danger still be present? Is there really even a danger in the first place? : :Thank you very much for your wisdom, advice and expertise! : :William in Colorado You could buy a medical grade 120V/120V isolation transformer to power your speakers from but that will still be fairly expensive but you will probably have to sort out the socket outlet for the plug-pack. You would still have the problem that somebody could unwittingly operate the system without using the transformer. Not a problem if you are the only one looking after and using the equipment. Ideally, you need equipment suitable for a teaching environment. eg. http://www.stethoscope.com/index.cfm...&ProductID=132 If the cost seems high then you will at least be supremely confident that nobody will have their safety threatened, and that can save a lot of worry about lawsuits. |
#14
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Help Question: Electronic stethoscope danger
Yukio...with our electronic digital stethoscope, the microbattery & cpu unit is
actually in the diagphram head...in short, the stethoscope head is the brains. It still uses the rubber-like tubing to the ear pieces so the danger is not the person wearing it...but the person whom the stethoscope is placed against & being listening to. William "Yukio YANO" wrote in message news:YOXwk.153910$nD.127330@pd7urf1no... PeterD wrote: On Sun, 07 Sep 2008 04:09:24 GMT, Yukio YANO wrote: WJW wrote: Hello...a quick question looking for a good suggestion/solution/answer, 1) I have a small rural nursing school; 2) I have a $500 electronic stethoscope (micro-battery powered) that can hear/play/record sounds using an I-Pod by using a direct wire/plug into the I-Pod external microphone jack; 3) I-Pod sounds are very weak and you have to be within inches to hear the sound during playback; 4) I need a room full of 10 students to hear the sounds from the stethoscope; 5) I connected it to a wall-plug store-bought powered I-Pod speaker sound system and it worked great...everybody in room could hear the sounds fine!; 6) Was then informed it could possibly be a major shock hazard (110 power from wall through speakers to stethoscope to person wearing (ear pieces) and to patient's chest (diaphragm); 7) So...now I'm back to Step 1 & 2... Any suggestions on how I could truly prevent a surge danger for under $100 bucks so that I can safely use the stethoscope and the powered speaker system? Would an automotive quick-jump power pack with 110 inverter work or would the danger still be present? Is there really even a danger in the first place? Thank you very much for your wisdom, advice and expertise! William in Colorado Just isolate the patient electro-mechanically from the stethoscope by placing the probe in a Plastic Baggie. The probe is most likely Plastic or Bakelite with a plastic or rubber hose anyway, A thin layer of plastic sheeting will not affect the acoustics ! Yukio YANO Let's say you were the patient... Would you wnat your life to depend on a plastic baggie? I don't think so. The correct solutions (either battery operated, or proper medical device) has been given. Surgeons have been doing this for generations, only they call them surgical gloves ! Standard, "conventional" stethoscopes were always electrically isolated from the probe tip by rubber tubing . If it was in the middle of a epidemic I would insist that a NEW baggie be placed on the Probe Tip . Where are you going to find and afford this Medical device ! Yukio YANO |
#15
Posted to sci.electronics.repair
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Help Question: Electronic stethoscope danger
On Sun, 7 Sep 2008 22:39:55 -0600, "WJW" wrote:
:Ross...good idea but not an option because we want the sound heard by :all...approximately 15 people at a time. We already have and use dual & triple :stethoscopes but they mean the task has to be repeated over and over whereas if :we could just broadcast for all to hear at once...presto! : :William I see. Looks to me like your best and easiest solution is the medical grade isolation transformer then. |
#16
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Help Question: Electronic stethoscope danger
On 2008-09-08, Ross Herbert wrote:
:Ross...good idea but not an option because we want the sound heard by :all...approximately 15 people at a time. We already have and use dual & triple :stethoscopes but they mean the task has to be repeated over and over whereas if :we could just broadcast for all to hear at once...presto! I see. Looks to me like your best and easiest solution is the medical grade isolation transformer then. Why not just use active speakers which are powered by batteries? |
#17
Posted to sci.electronics.repair
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Help Question: Electronic stethoscope danger
WJW wrote:
Archon...Good idea but I can not tell if the Belkin requires the cigarette plug or can it operate independently with internal batteries? William "Archon" wrote in message ... Jeff Liebermann wrote: On Sat, 6 Sep 2008 11:09:04 -0600, "WJW" wrote: In actuality...all the I-Pod does is play/record sound (and not very well due to the frequency/tones of heartbeat & pulse)...so...the digital stethoscope is self amplified and could operate without the I-Pod if I had a battery powered stand alone speaker system I could plug into directly with the scope...or as you suggested (great idea), a wireless transmitter that could then relay the signal to a good powerful receiver. Any suggestions (brand/model) along either line? Nothing specific. Google for "battery powered speaker". Lots of hits. I would be tempted to suggest a battery power boom box or karaoke box. What I'm worried about it that someone is going to run it with the stethescope while charging the internal batteries. Too big a risk, so we're back to wireless again. Look at the wireless microphones available for persentations. They're usually in the commercial sound business sites. While most have a built in microphone, there are a few that allow external mics. They're unfortunately kinda pricy. You might do better with wireless speakers that are made to run off a hi-fi. You didn't supply any interface specifications, but if the stethescope puts out home hi-fi line levels (about 0dBm), one of these should work. I gotta run, but I'll see if I can find something later today. This would hopefully suit you, they are available in Walmart and work quite well, I had one on my mp3 player in my car for ages due to my CD player being bust. All you need is your radio boombox tuned to the transmit signal. http://catalog.belkin.com/IWCatProdu...duct_Id=166903 Hi, It has 2AAA batteries inside, doesn't need the 12v plug. The batteries last a reasonable time as I think it shuts down if there is no audio signal. Mine was an earlier version that I had to switch off but it still lasted a good time. |
#18
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Help Question: Electronic stethoscope danger
On Mon, 8 Sep 2008 11:00:15 +0000 (UTC), Mika Lindblad
wrote: :On 2008-09-08, Ross Herbert wrote: ::Ross...good idea but not an option because we want the sound heard by ::all...approximately 15 people at a time. We already have and use dual & triple ::stethoscopes but they mean the task has to be repeated over and over whereas if ::we could just broadcast for all to hear at once...presto! : I see. Looks to me like your best and easiest solution is the medical grade : isolation transformer then. : :Why not just use active speakers which are powered by batteries? Typical scenario: Crowded classroom, busy instructor.... Oh bugger! flat batteries... Now where did I put those spares? Sh.t! I didn't buy new ones after I last replaced them with the spares I had. Now do you see? |
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