Equivalent

[alain68700]

Hello, Mohandes.
I already told you, I no problem with the transistor J113.
It is you, who want to put on your detector equivalents.
Here's my advice to you, put the original component before and to finally run your detector.
And then you could change seeks to see if there are differences with your equivalent.
The only ones I did not values are styroflex capacitors.
Well, I think you answered quite clearly.
Otherwise think to find a good translator.
Good day.

[mohandes]

Hello to my friends Davor and alain
first Davor:
thank for your attention.ok I understand the caps are electrical and 1000HY50 means 1000pF=1nF 50volt
and thanks about the equivalent the transistor.and i dont Know common type but completely name &139 j113.
the coil. my main problem is that.can you help me?
about the picture.i have not camera and i take by mobile?
thanks

[mohandes]

Hi Alain
my means that I need the equivalents no you.and think maybe you havenot and need to use equivalents.
you say: Well, I think you answered quite clearly.but Davor says different . i write above , is it correct?

have good time my friend

[Davor]

As for J113, it is a N-channel switch, and by nature it is a FET. Due to it's symmetry it is called a switch. I expect BF245 to work well in it's stead.

As for coil, it looks like a mess. It is a DD coil, that much I can see. I guess that odd pieces of cable are some sort of repair that did not go well? I think you are at loss here because fixing a detector with a working coil ... OK. Fixing a coil with a working detector ... OK but tricky. Fixing both ... not OK.

Can you get a working coil or a working detector? Fixing both of them is very demanding.

Regarding taking pictures, just place a thing you want a picture of on a flat surface, say cardboard, in front of a white wall somewhere outside, and take a sharp picture. Every camera has a minimum distance so try to find out what minimum distance produces sharp pictures.

[mohandes]

thanks Davor
now can i use 1nF polyster caps(mkt mark)instead 1000HY50 and all other.example150Hy47 means 150pF ,allright.

ok i first repair the pcb next go to repair coil.
you should know i set the parts and connect battery to it but dident work.why?how i know where it has error.maybe the capacitors have problem,or transistors are burn,...
thanks

[Davor]

I'd say your best bet right now is comparing the diagram posted by scs at http://www.geotech1.com/forums/showt...503#post165503 with your detector. I found great similarities between your detector and that diagram. Part numeration is different, but layout is mostly the same. Some parts are a bit different, but perform the same function, and the only big difference is a small PCB with CD4046 that I can't say what it does exactly.

In case a coil is also designed as drawn in the schematic, you are in luck. The coil seem to contain only a single capacitor for a Tx tank, and in case it is not burnt as well, you'll be able to fix it.

So I suggest you start by drawing the parts of schematic using the scs' diagram as a help and see what values are there. Start by the parts that are burnt and see what function they perform.

[mohandes]

ok
this schematic have a few simillar to my detector.look,i have pcb and set the parts of them but some of the parts is burn or...becuase when i connect the battery dont work.help me to equivalents of capasitor but i dont understand real value of them.if i change the burn capacitor and transistor more better also i find the problem without the burn capacitors & transistors.you said me about j113 and capacitors but the capacitors i dont understand.
excuse for my english and if you can write for me easy language, please.
regards

[Davor]

OK, simple English.
What instruments do you have? Oscilloscope?
Can you measure resistance? Inductance? Capacitance? Voltage?

Let's fix coil first! Make some photos of the coil (white wall outside, on flat surface. Perfect balance is not very important to fix detector, but coil must be in working condition. Not perfect, but working.

[mohandes]

Hello dear Davor
i take many photo and put here and CSCOPE metadec repair please see them and help me.
regards

[mohandes]

http://ir2up.ir/up19/bf613622094501.zip
this is my photos

[Davor]

The coil...

It is obvious it was exposed to moisture, but most probably it is not too much damaged. You have the diagram of the coil posted before. Colour codes of the wires will help. First you replace the cable. Find a triple coaxial cable as used for video or SCART connectors. There you have all wires you need and it is more flexible. Use the existing connector, but first clean it properly.

Make a simple oscillator. You will find on this forum as coil tester http://www.geotech1.com/forums/showthread.php?18568 Confirm both coils, Tx and also Rx oscillate, and find what frequencies.

If your coil works, we'll fix your detector next.

......

Being in Iran means you are not able to obtain ethyl alcohol, right? Can you get denatured alcohol, as used for lamps? It is also used as shellac thinner. It is a mixture of ethyl and methyl alcohol. Pure methyl alcohol is not good. Iso propyl alcohol is OK, but it must be 99% (hard to get). Don't use gasoline. I see your boards have some sticky residue on them and it will be very good to clean them properly before you continue. Use a brush and alcohol and clean it well.

If you can't get alcohol of any kind, can you find freon? I'm not kidding - it is the best solvent for cleaning PCB-s. There are only ecology freons available so it is OK. It is expensive, but so are speciality solvents.

I can't see any obviously burnt parts.

[mohandes]

Hello dear friend Davor
it make time for me.maybe one week
1-I clean this board
2- I buy the cable
3-I test by oscilloscope
tanks for your guide.
regards

[Davor]

2.5 - you make a coil tester oscillator to see if your coil oscillates and where, see http://www.geotech1.com/forums/showthread.php?18568

[mohandes]

ok
thanks my friend

[mohandes]

i got baracuda parts but many parts dont exist so heck this and tell me please:
2N5485=????????
MPS 102=bf244 ,so i buy for it bf256 correct?, and bf245=bf256 ?
MPS A13=?
MPS 102=?
bc517=c2062cs ,correct?

and i buy lm358 too, is it equal above part?which of them?