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About ben11

  • Birthday 09/06/1988

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  1. HI everyone. i finished building the amplifier but it still did not work. i checked and checked for any errors but i corrected the ones i found and did not fine any again , but it did not even work poorly.the signal became worse. i thought of an op-amp. is there one that i could use that will limit the number of parts and maybe limit possible errors? please can someone give me an idea of where i could fine small value ceramic capacirors.i needed one of 2.2pF but i only found one of 2pF(and is the one i am using) in one old microphone.it is not solded in any of the shops in the parts market here.In which old equipment can i fined them? thanks -ben-
  2. hi. i bought a new soldering wire and it is so so good.it solders very well it acyually has much flux in its core. please MP(or anyone) can you go back to the project(RF circuits:then Tv Signal Amplifier) and read the last chapter and please tell me what a feed through capacitor is and how i should used it. thanks
  3. thanks for your help. i hope that if i find the flux it will make the soldering easier. i also hope it is not expensive.
  4. i do not know. i am just writing so you do not feel abandoned. i can advice you to edit your post and write your request in clear ,good english. -ben
  5. thanks. i will put it in a box. since i did not have a pcb, i bought a plaque a essai as it is called in french.it has many long strips of copper on it with many holes along the length of each path. i tried soldering some components to the board but it was so so so so difficult to do that i only soldered one lead of a resistor and it was by mistake and i couldn't repeat the mistake. the project says you should put the soldering iron on the lead then put the soldering wire at the point where the lead emerges from the copper side of the board and that the soldering wire will melt taking heat from the lead and that this proccess should take not more than five seconds.i have a 60WATT soldering iron.when i do these the soldering wire does not melt and i fine myself heating the resistor for more than 15 seconds. i do not know if the problem is with the soldering wire(ie does not easily melts) or i am doing it badly. even when i melt the wire directly with the solder,it does not adhere to the plaque d'essai. please tell me what to do and please also tell me other methode of soldering. thanks.
  6. do you think i really need to solder the components together? what about the earthing? i took the point earth as the negative terminnal of the battery as they are on the same wire. you can look at the circuit in the RF projects , there you will see tv signal amplifier. thanks for your help.
  7. I think i did the connections very well.i mounted the circuit on a cartboard paper but i did not earth the circuit.though i did not solder the transistor to the wires i wrapped the wires around the leads of the transistors very firmly so it is imposible that there is an open circuit.
  8. can the connecting of small capacitance capacitors not instead help? what if the circuit is so big that the connecting wires cannot give rise to any capacitance between them?
  9. Hi everyone. I need a pcb of about 5by5cm for a single transformer amplifier.i tried to get most of the parts but i have not got the pcb and i badly need it for the circuit to function properly as it is a tv signal amplifier. if someone can make it for free and send it to me by post i will be Very Very grateful. if no one can do it for free i can send the person about 8dollars as that is what i can afford. you can send me a private message on this. Say Blessed. Thanks
  10. is there only one type of series rectifier diode? most part sellers here are very dull.all they want is tha name and number of a part.can you give that to me so i can try to find? thanks for the spelling.
  11. thanks. i know about the stay capacitance but i want to know how they come about due to the large circuits. i did potential dividers in high school.lets say i want to reduce the voltage to the sholder by half, do i have to connect two resistors in parallel,then connect the shoulder across one? do you know anybody that loves making pcbs? (forgotten how to spell shoulder)
  12. hi. i just want to know what causes a circuit not to work if it is build bigger than the size stated in the circuit diagram.i just buid a tv signal amplifier but when i used it on my tv, the signal was even worst.it was about trice the original size. i build it on a cartboard paper as i did not have a pcb. i tried buying one(4.5by5.3 in dimension) online but it was very expensive at about 26dollars but including shipping, but 10pieces will cost $36 but one is not $3.6.there is a money sendine company called money gram in my country cameroon.the minimum amout of money you can send is about $8.if there is someone that can make me a pcb and post it at this price,i will be very greatful as it looks like my circuit will not work without it. i have a BFR72(or 92 )transistor.it has very short leads.i am afraid i will over heat it while building the circuit as i have only a 60W shoulder.are the transistors very resistant to heat?if not what can i do to make the connections without destroying it. thanks
  13. example:i saw what looked like a transistor but it had 2 lead.it had labels on it.it was very protected.what can i do to discover what it is?
  14. hello. when i open old devices to try to understand how they work, i see many components i do not know what there are.but they have labels on them ie numbers and letters.is there i site that you can just write the labels of the part and you get full details about the part? thanks. -bennett-
  15. hello. i saw a project hear that really interested me (tv signal amplifier) i got all the parts that i need and constructed the circuit.i did the right connections but the tv signals was even more blured when i tried it.then i iwas told i had to respect the dimemsions of the circuit given in the project.to construct such a small circuit i can't do it witouht the PCB.So if there is someone that can construct one and send it to me i will be so so greatful.it is just about 4.5cm to 4cm. thanks. -Bennett-
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