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    9V BATTERY CHARGER CIRCUIT

    Thanks. The 9v batteries I use are 280ma 8.4v NiMh. So would I use a 10v zener reference  instead ?. Also What resistor would I use to give me 28ma c/10 in this circuit. Thanks.
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    9V BATTERY CHARGER CIRCUIT

    Hi, found this circuit on the net. I have attached the schematic and a drawing of the pcb layout. Just need to know if it will correctly charge a 9v battery safely, and if the pcb I have drawn is correct. Thanks in advance for any help.
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    TESTING A 40673 DUAL GATE MOSFET

    @Hero999 Thank you so much. I have tested the 40673 re your instructions and it is indeed faulty. Thanks and regards
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    TESTING A 40673 DUAL GATE MOSFET

    Hi, thanks for the reply, though I should have mentioned that I am a complete novice in electronics. I am not quite sure of what you mean, do I apply 5 volts directly to one of the gate legs ?. And if I see a high resistance ....is the mosfet in good condition ?. Sorry for my lack of knowledge...
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    TESTING A 40673 DUAL GATE MOSFET

    Hi, please can any one tell me how to test if a 40673 mosfet is blown. Can I test this with a digital multimeter, if so how do I go about it ?. Pic attached. Thank you.
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    HELP NEEDED WITH FUSE RATINGS FOR ATX PSU MOD TO LAB PSU

    Great, thanks for the schematic I can visually see the problem now. The thought of getting 22v variable sort of took over when I spotted this pc Atx mod on other sites. But when I think of it, I probably wouldnt have needed that voltage much in the real world. The -12v , & in fact all other...
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    HELP NEEDED WITH FUSE RATINGS FOR ATX PSU MOD TO LAB PSU

    Hi, Thanks for that. In view of your knowledge on this matter I have decided to do away with the -12v and +12v idea to get variable voltage from 22v down. I wasnt aware of the theory of how it would behave when used. Would I now be ok to use my variable pcb to vary the +12v and black 0v gnd...
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    HELP NEEDED WITH FUSE RATINGS FOR ATX PSU MOD TO LAB PSU

    Hi, thanks for the reply, the psu is showing correct voltages on all post terminals.As I have fitted an lcd volt meter to the face off the psu cabiinet. I think the lcd meter could be the small load required thats making the Atx give the correct voltages. The -12v gnd from variable pcb is...
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    HELP NEEDED WITH FUSE RATINGS FOR ATX PSU MOD TO LAB PSU

    Hi, please could some kind soul help me with correct fuse ratings to protect the atx psu when connected to electical items. Picture is attached. I:E if any attached items, go bad , I need the fuse to blow instead of the atx psu continuing to give loads of current. Thank you.
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    Need to trigger A reed Relay with nearby RF

    Hi, can any one help , I want to build a pcb with a reed relay that will trigger on any transmitted RF signal  (front end protection in mind ). Hope this is possible, rather than using 12v tx on rear of radio to trigger the relay. This way it would be more portable to connect to any second...
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    SLIGHT HELP NEEDED WITH ACTIVE ANTENNA CIRCUIT

    @audioguru Thanks for the reply. What do you suggest adding to this circuit to improve it ?. Also what about my original question on Axial inductor instead of air or ferrite wound coil for the 20uH ?. Regards
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    SLIGHT HELP NEEDED WITH ACTIVE ANTENNA CIRCUIT

    Hi, please can some one answer wether I could use an axial inductor in this circuit instead of a wound coil for the required inductance of 20uH ?. Drawing attached. Thank you.
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