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transformer help

[unit25]aaron

New Member
Nov 10, 2015
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0
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Can someone tell me how to wind T1 & T2 in the diagram the instructions say :

T1 5 Watts


The 5-watt version has a much lower Base impedance. In this case it is around 1 Ohm for each transistor. If the input is 50/75 Ohms then the impedance ratio is about 64:1+1 which is a nice round figure of 8:1+1 turns ratio. 8-turns primary winding and 1+1 turns secondary. This means 2-turns with a centre-tap. Use a little thicker wire for the lower impedance windings.

T2 5 Watts
The 5-Watt version output transformer must match 8 volts (RMS) at 625mA = 12.5 Ohms to the output of 50/75 Ohms. Interesting that for 50-Ohms the impedance ratio is 1:4 so the turns ratio is 1:2 (2:4). The primary is tapped, so 1+1:4 is the correct turns ratio. The primary consists of 4-turns with a centre-tap (2-turns + 2-turns) and the secondary of 8-turns.

This is the first time doing this.
Here is the site im getting the info from : http://sm0vpo.altervista.org/tx/rf_pa_cct_00.htm
 

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If you are using that on a transceiver you might be disappointed. That has no switching from transmit to receive. What is it you are trying to achieve?
 

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