IGSL

[golfnut]

Hi Hugo, If Bernte one is using an IGSL, I am right.

If Bernte one is using the schematic in your post YOU are right.


S

[hugo]

@Bernte_one : Try this http://www.deephaven.co.uk/lc.html to calculate your capacitors.

[Pompey]

Use this to adjust Rx coil! It`s easy to make and very accurate.For transistors you can use any type like BC547 (NPN) and BC557(PNP)

[hugo]

@Golfnut,

I think there is a mistake.
330nF with 0.38mH gives 14.21 Khz (not for C2 but for C1, C2 is for 9V filtering).
And guess what, 14.21 Khz multiply by 1.166 gives 16.56 Khz just like 130nF with 0.71mH.
but the real frequency will be 16.37 Khz with 133nF (100nF + 33nF).
With a manual selection of the caps, you can easily reach the correct value.

Regards,
Hugo

[golfnut]

bernte one..

The Tx on IGSL is 14.6kHz (it is on the schematic)
The Rx is 16.3kHz ..... ( from 1/(2 x pi x sqrt(LC)) L was 6.5mH C is combination of C4 and C43 (4n7 and 10n (which is 14n7))


So in this IGSL OFF resonance design .. Rx coil and cap is 1.7kHz Higher than Tx.

You are right about the ratio of Tx to Rx being approx 1.2 (actually 1.116) BUT, Tx is lower, and RX is higher.

For you to resonate your coils at original IGSL design frequencies - with your Tx coil at 0.38mH and Rx coil at 0.71mH

With standard values
C1=3u3
C2=330nF
Gives a Tx of 14.9kHz


C4 = 100nF
C43 = 33nF
Gives an Rx of 16.4kHz

Difference of 1.5kHz This should be fine.

steve

[bernte_one]

Apperas to be some confusion as to what Tesoro coils can be used with either the TGSL, IGSL-Tesoro, IGSL-Musketeer.

Any one make a short list of which coils are compatible, 4 pin, 5 pin......?? This would be very helpful for those who cannot build their own coil.

normally the 5 pin tesoro (older models) with tgsl

the 4 pin newer coils with igsl musketeer


but cant say you which minelab coils without modifying the tx and rx caps

my excelerator 2 with 0,38 nad 0,71 mH works not
the supersearch coil for my old musketeer x cant work it has something of 1,1mH and round 20mH

the diy coil i tested works good 1mH and 14,7mH

i thought i give it up to make diy coils with so much windings and maybe also vlf detectors building coils or modifying original ones takes too much of my time

i think i wil concentrate to pi detectors coils are more simple

maybe i use my excelerator 2 with one of my pi machines

[der_fisherman]

Capacitor conversion and codes

Looks like a cap but, not 100% sure on the value.

Its a cap in Picofarads 334 = 33 and 4 x 0(zero) = 330000 pF.
OK?
Regards
Andy
PS. If you look around on the web there are simple tables around to download that help you to convert such a value into say nano Farads for ordering....
Look here:-

http://www.justradios.com/uFnFpF.html

http://www.turretboards.com/capacitor_conversion_chart.htm

http://www.calculator.org/property.aspx?name=capacitance

http://www.radio-electronics.com/info/data/capacitor/capacitor_conversion_chart.php

[SVEN1]

Not sure what part on PCB marked 334 is??

Looks like a cap but, not 100% sure on the value.

[SVEN1]

Coils question

Apperas to be some confusion as to what Tesoro coils can be used with either the TGSL, IGSL-Tesoro, IGSL-Musketeer.

Any one make a short list of which coils are compatible, 4 pin, 5 pin......?? This would be very helpful for those who cannot build their own coil.

[bernte_one]

Hi Bernte one, If I have it right - you want to tune your Tx onto ~ 14khz
And your Rx onto approx 16khz

You are using a coil with L values outside of the normal IGSL coils design of approx 6mH.

Steve

hello golfnut
written already above:
i calculated the frequencies of
tx 14.001 kHz (ideal would be 1,2 *f rx 13.870 kHz but cant find better caps)
rx 11.559 kHz

or did i confused the frequency shft of rx and tx

should rx be 1,2 of tx? i thought it were other way - is that my failure

coil that i have has 0,38 and 0,71 mH

[golfnut]

Hi Bernte one, If I have it right - you want to tune your Tx onto ~ 14khz
And your Rx onto approx 16khz

You are using a coil with L values outside of the normal IGSL coils design of approx 6mH.

Steve

[bernte_one]

ok thx andy
so wide so clear i understand

but can anyone tell me if i co the right way to set my tx and rx to the fequency with the caps

i did i run the wrong way

regards

[der_fisherman]

Elko with too much voltage??????

.....elko with elko but i think its only a problem of an elko with to much voltage
if i kow if i can replace the one elko with a mkt i would try it......
.......any other advice welcome

I will say it again:-

The voltage marked on an elko (Electrolytic Capacitor), is a value that must not be exceeded by the circuitry where it is connected. If you are expecting say 24 volts max, a 25 volt Capacitor is a bit close, a 50 or 60 volt would be best!!!

BUT, it will not give any problems if say you have a 50 Volt Cap, in a 10 volt circuit.......

Its a bit like driving! For example, if the speed limit is 50 KMH, as long as you do not exceed 50 KMH, you are OK. But if you drive at 60 KMH and you will be in trouble with the police!!!!!

The only difference is that for the same value, for the same type, from the same company, the 50 volt version will be (slightly) bigger than the 16 volt version.....though modern caps are getting smaller as the technology improves.

Do you now understand fully? Please ask if I was not clear enough.

Regards

Andy

[bernte_one]

thx andy

i have only changed to thetypes they were build in before
mks to mks (one mks i replaced with a mkt more precious)
elko with elko
but i think its only a problem of an elko with to much voltage
if i kow if i can replace the one elko with a mkt i would try it

it would be a dream to get my igsl working with that excellerator coil i have

any other advice welcome

[der_fisherman]

Electrolytic Caps

hello all

i have a little problem
i build the musketeer version and changed following parts
c4 220nf mks
c43 47nf mks prallel gives 267nf

c1 680nf mkt
c2 680nf elko 50v in serie give 340nf

coil is excelerator 2 with rx 0,71mH and tx 0,38mH (if right measured?)

but dont work

i calculated the frequencies of
tx 14.001 kHz (ideal would be 1,2 *f rx 13.870 kHz but cant find better caps)
rx 11.559 kHz

it should work or is there any failure in my thoughts a is this a wrong elko, maybe a 50v elko is to much ?

regards

Someone else can answer about your main problem better than I can, but with regard to voltage of Electrolytics, the higher the VWDC (Voltage Working DC), the larger the capacitor. There should not be any other problems due to volatge......

As long as the VWDC is not exceeded in the circuit ever, that will not be a problem. If it is exceeded, an Electrolytic can explode.....

What might be a problem is that its an Electrolytic that you have used....also, I have not personally seen Electrolytics with the values you mentioned as there are far "better" types of capacitor that cover these ranges. (I am prepared to be corrected on this point, I am only speaking from my limited knowledge).

This might imply that the frequency is incorrect, though I have to admit that I have not calculated the frequency with your values though, too lazy!!

Generally speaking the Electrolytics cover the higher ranges of capacitance needed in circuits....

What "type" were the ones you replaced? If not Electrolytic, that may be your problem...

You should always use the same "type" of capacitor (best quality) if possible unless someone like Ivconic or Simon or Eduardo says to change it......

Electrolytics have some drawbacks.....leakage being one of them if I remember correctly.

Regards

andy