Hallo alle zusammen,
ich habe mir heute eine Rahmenantenne gebaut und stehe nun vor der Farge wie schließe ich diese auf der Amp. Platine an ?
Ich habe ein PCB 5 Vers. 6.
Muß ich auf dem PCB Board noch etwas jumpern ?
Für ein paar Tipps wäre ich seher dankbar.
Viele Grüße Thomas 
Easier to discuss when we have a drawing.
I suggest fig. 3 or 4
.. both running at a relatively low impedance - gives a flatter frequency response
If you have no Shield, so ignore it.
/richo
Hi richo,
it is good summary on your attached circuit collections. I tryed to explain for myself the differences of the circuits. But can you explain the differences in the behaviours of this circuits?
fig 1: the coil of the ferrit antenna connected to the + and - input pols of the op amp, and it has "independent" grounding of the shields on the ferrite.
fig 2: the shield grounded with the - (negative) input of the op amp.
fig 3: the shield grounded with the + (pozitive) input of the op amp.
fig 4: the same as fig 3, but the + pol connection has a 2,2K resistor
fig 5: the + has the 2.2K resistor in grounding, and the - pol direct grounded with the shield.
fig 6: this is the 2 Wire antenna configuration
t.janos
(+) have 100Kohm imput impedance
(-) have 2,2Kohm imput impedance
Low input impedance changes influenced by self resonance of the antenna - it flattens out.
The 2.2 Kohm to be seen as an attempt to destroy the Q of the antenna and get a better frequency response.
I have simulated the different connectivity options, and show here the results - hope it explains what happens 
/richo
...and the curves collected
/richo
Hallo richo,
many thanks for your help !
I'm going to look at your pictures and then I'll report back !
best regards Tom
