Emad

Hi all Ihave made the original ,the corrected and the elect. steth. 2 about one year ago The original didn t work and the other two worked. The best one was the corrected circuit. The stethoscope should hear the sounds between the 1st and 2nd , and the 2nd and 1st heart sonds , like murmours as systolic and diastolic , also clicks and so on. So there shoud be no noise . I hope to find a new project using 3v supply and a small head phone like that used with mobile . This will be more practical and I can use it in my clinic. Thanks to all especially audioguru.

Hi all I made these circuits many times without the part involving the bipolar diod and they were operating. About three times they suddenly become badly operating.they respond to knocking on the diaphragm of the stethoscope but not to the heart sound.I dont knoww the cause. I hope you give me advice. Thank you.

Hi audioguru many thaaaaanx Realy I dont know how to thank u. Forgive me my english is so bad to do that

Hi Audioguru sorry for being back so late I want to ask about modifing a circut working on 3 volt and used as an hearing aid as a stethoscope?? this circuit is present in this site http://www.electronicsforu.com/EFYLinux/circuit/aug2003/CI-2-hearing-aid.pdf Shoud it do well if a filter circuit is added between transistor 1 and 2 ????? Many thanx

Hi Audioguru If I want to use the 220 volt supply for the stethoscope,what rectifier circuit could be used . I hpe you post it. Is there any modification in C7 and C8?????

Hi Audioguru Ihad reversed the variable R and had controle on volume . The sound is good in about 1/4 the range of the volume controle or less ,then there is mutch distortion. By putting 1k risistor paralell to R4 the noise disappear but heart sound become weak and respiratory sounds are not percepted. I think this circuit needs some slight modifications that I dont know. thanks for help.

Hi Audioguru. I built this circuit with the TLO72. There is mutch noise. When lowering the volume there is a sound like hissssssss ,then after slight raising of volume heart sound is very laod and there is nearly no effect of increasing the volume . My mic cable is about 2 meter long but it is well sheilded. I use a real stethoscope head that already amplifies the sound before coming to the mic. What about putting R3 again in the circuit???? and what is your advice???

Hi Steven These circuits use propes that shold be connected to the body. Is there acircuit producing pain relief without contact to the body??? Many thanx

Thank you Steven

Have anyone heared about a circuit that relieves pain ??? If there is a circuit like this pls tell me . THANX ALOT.

Thank you Audioguru. I ll try 4.7nf tomorrow

I tried 20 nf for the two and then100 but the heart sound became very fiant in the both attempts. The circuit is good with its original capacitors. I had put a link to your project in an arabic electronic forum. I dont know shold I have been first taken a permission from you or not ???/ If so I can delete it . her is the site: http://www.arabteam2000-forum.com/index.php?showtopic=49466

Hi Audioguru You knoe I built what is called the corrected circuit using 2 TLO71 and LM386. It works well. Is the E.Stethoscope 2 the same. ?? Have you built it?? Which battery is connected directly to the LM386??That one connected to 470 uf or that connected to 1000uf. I wonna tell u that the circuit named E.auto stethoscope is bad,I asked u about it before.

Hi Audioguru I built the circuit named auto stethoscope. It works but your circuit is mutch better . I want to ask about C7 and C8. You said 1000uf for C7 and 100uf f or C8 I noticed that one battery became very week. What is the cuase??? Also could some components be changed to make the tone of the sound less huge?? Many Thanks.

Audioguru. Thank u again . I wonna tell u that I built the circuit without the IC which is connected to the bipolar diode.I wanted to decrease the size of the board and also the mistakes.