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Help with Transformers & Inductors for HF

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Vaibhav Birit

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I Downloaded this circuit for 20m, 4W QRP transmitter from a website, some 2 years ago. It no longer exists on that site.
I am in the process of building this circuit. However i am facing a problem realising the inductors & transformers mentioned.

The following information has been provided about the inductors

L1: 9 Turns of 24SWG insulated copper wire over 8mm diameter oscillator coil former with ferrite bead.
L2: 3 turns of 24SWG insulated copper wire over coil L1
L3: 9 Turns of 24SWG insulated copper wire over 8mm diameter former with movable ferrite bead.
L4: 14 turns of 20SWG insulated copper wire over 1.5 cm dia. PVC former(The coil is to be Tapped from the 9th to 10th turn from the top end.)
RFC: 12 turns of 36 SWG insulated copper wire using TV Balun core.

from the above decsription it isn't very clear what type of cores are required for L1, L2, L3
L4 & RFC are understandable.

I built this with my own interpretation of L1, L2, L3 but found that the transistors were becoming Too Hot even at low voltage (of 6V)

Can anybody throw any light on how L1 L2 L3 should be. Or else tell me how the design takes place for such a configuration so that we can calculate the necessary values by using formulae.
 

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