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Hi,
metallic case ??? PN2222 in metallic case ??? strange.
Anyway, metallic case 2222 are 2N2222 (to-18 ). Look at the picture.
The small piece outside indicates E, the central is B and other C.
Best regards,
Max
Usually the 2N2222 and 2N2222A are available in TO18 metallic case, and the PH2222A and PN2222A are available in TO92 plastic case.
TO18 has base as middle pin and emitter near small lug on side.
TO92 has collector as middle pin. With flat side down it's B C E, viewed from below.
At least the plastic ones should be easier to chew.
hi if you have problems for maxime deep detection of your gs
maybe wrong value resistences, or interchanged , use precision resistances value
what say ivconic? 1/4 watts or 1/2 watts i not know
you put other substitutes in ics lm at tlo originales sure! this is the problem
problem coils can,t
ivconic can say your messures point for point in outputs of ics to ground
apologies for my bad english
nelson revise los valores de las resistencias, pudiera ser que algunas no dan los cercanos porcentajes, si estan muy corridos ponga otras mas apegadas al diagrama, pregunte si ivconic puso de 1/4 watt o de 1/2 watt, y si pusistes ics substitutos procura poner iguales como lo hizo ivconic, es muy dificil poder igualar un circuito que fue optimo por casualidad, asi que procura copiar identicamente el circuito de ivconic, y quita amperaje, el regulador solo regula los voltios y no la potencia de amperes, eso te puede traer un problema, 4 ampers es demasiado, y si das un roce a corto quemaras muchos componentes, te mando un saludo
Usually the 2N2222 and 2N2222A are available in TO18 metallic case, and the PH2222A and PN2222A are available in TO92 plastic case.
TO18 has base as middle pin and emitter near small lug on side.
TO92 has collector as middle pin. With flat side down it's B C E, viewed from below.
At least the plastic ones should be easier to chew.
Hi Qiaozhi,
TO-92 (like other packages) is just referred to package dimensions, leads spacing etc so geom. specs of it... not to pinouts, as for sure you already know.
There are different config pinouts for TO-92 packaged transistors, as I wrote in previous posts, look at picture below.
Then there are also strange things related to non-standard devices and different from expected marking on some asian manifactured components.
this post just to explain that wire diameter is not so important in homemade.
I've made total of 3 x DD22 during bandido experiments and testing.
Now have just the DD22 that I've described (120+120 turns 30AWG).
I've made , with same dimensions other 2 DD22 coils using 0.275mm (0.30mm with varnish) and 0.30mm (0.33mm with varnish) diameter wire.
Of course, I've made some more turns to get about right resistance range (18-24 ohm) required, and also changed caps... tested various stuff.
I don't remember now exactly data about turns but resistance was 18-20 ohm for both tx and rx in both coils. I haven't use shields on them... just tested without shields and results were good.
I remember I get 1eur coin at 28-32cm using same geometry of actual coil with both. All I've to do was:
- getting right resistance
- getting about 10KHz on TX oscillator
- getting a good null
At the end, I choose 30AWG coil cause I get it goes better with original cap values (with slight mods. 3-4 nF) and get maximum depth (about 30cm for 1eur coin underground with that DD22). Then recovered wire used for the other 2 coils... cause I feel good with my actual and have just 1 suitable coil-container to seal.
My experience is the proof that you can make good coils with higher gauge wire just increasing some turns and get them working in right conditions (frequency and nulling). I got good results on 0.275 much like 0.25 and only have some troubles getting 0.30 working (required heavy caps. mod)
There's no magic about wire gauges...
What you could do with 0.25... you could do with 0.23, 0.24... 0.28!
And all this cause you don't need standard coil! Your is an homemade... you can play with caps... and turns as you want.
I mantained that DD22 (0.25) only cause I got an original coil and then need standard caps on front-end! Also my 8'' round concentric is much like original coil from tesoro! Same reason.
So... don't become crazy with wire gauges... you need "about" 30AWG... but it's not really critical. Belive me.
Not meaning to change the subject, but....
Here is a conductive glue recipe that might come in handy. I'll give it a try when I can. But you can still try it. Maybe it can be be used for bonding aluminum foil to copper shielding?
i.e. Faraday shield to ground? http://www.instructables.com/id/EYA7...SXBI/?ALLSTEPS
Hi nakky,
Ok, I'll check ivconic's diagram and make compare with schematic on pdf.
OK: found R40 connected to anode of D12... not to output of comparator (catode). But why ?
Best regards,
Max
Max i am not technical,i build my one small GS and it did not working good.A frind of me look at it and now it is working good.(I am a Japanishe).Ivconic will you explain?Grt Nakky
Max i am not technical,i build my one small GS and it did not working good.A frind of me look at it and now it is working good.(I am a Japanishe).Ivconic will you explain?Grt Nakky
Hi nakky,
OK , sorry, question was for me...not for you... I was thinking about connection of feedback resistor...
(rethoric question ???)
I think that Ivconic has much more experience with this schematic than me (just watched few minutes at now)... so he could give some light about.
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