my last post transistor circuit posted (see "Differential DC amplifier circuit" topic) was received very helpful advice from people (like Ron H, chesar1 and the other).Now it comes again:
I've constructed a standard circuit to perform a similar task: amplify a ac signal.
The first circuit called "single stage Audio Freqency voltage amplifier", it was tested to have a gain of 60 as I expected. Now the fun part came in, when I setup a "multistage audio frequency voltage amplifier" based on the first part, the 2nd gain returned as I calculated, but the 1st gain which is the gain of the circuit 1 returns to 40 instead of 60?????????
I know some guys here have a better undertanding of transistor than me (as it is proofed) so please help.
Attached file: 4 files included (two are in doc format which show you the real picture of the circuits constructed in the case you don't you multisim like me, the others ,of course, are in multisim format 8, so anyone got multisim can test it straghtaway)
I've constructed a standard circuit to perform a similar task: amplify a ac signal.
The first circuit called "single stage Audio Freqency voltage amplifier", it was tested to have a gain of 60 as I expected. Now the fun part came in, when I setup a "multistage audio frequency voltage amplifier" based on the first part, the 2nd gain returned as I calculated, but the 1st gain which is the gain of the circuit 1 returns to 40 instead of 60?????????
I know some guys here have a better undertanding of transistor than me (as it is proofed) so please help.
Attached file: 4 files included (two are in doc format which show you the real picture of the circuits constructed in the case you don't you multisim like me, the others ,of course, are in multisim format 8, so anyone got multisim can test it straghtaway)