The Fisher 4400 FM Receiver
Posts: 1,114
Threads: 14
Joined: Feb 2013
City: Irvington, NY
Ron, you might also check the values of R22 and R48 and compare them to the corresponding ones R21 and R47 on the other channel. Each pair of resistors form the negative feedback network which determines the overall gain of the amp. If the 100 ohm resistor has gone up in value it will decrease the gain of the amp. Approx overall voltage gain is 100 + 2700 / 100 = 28.
Because of the negative feedback, minor differences in the hFE of the input transistor will have only a small effect on overall gain.
Messages In This Thread
RE: The Fisher 4400 FM Receiver - by Mondial - 02-20-2014, 09:20 PM
Users browsing this thread: 3 Guest(s)
|
|
Recent Posts
|
|
54C Complete Teardown/Rebuild
|
| I don't think that I have encountered a 12Z3 before, curious how it uses one of those but includes a #43, which is a 25 ...Arran — 02:17 PM |
|
HiFi (Chifi) tube amp build - but my own design.
|
| It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM |
|
Philco 71 Code 125
|
| Hello,
I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM |
|
Stromberg Carlson 1500 Squeal
|
| And life just keeps getting more complicated.dconant — 07:57 AM |
|
54C Complete Teardown/Rebuild
|
| Hello Roy,
here is this one
sincerely Richardradiorich — 12:45 AM |
|
54C Complete Teardown/Rebuild
|
| Richard,
Had grabbed it already but thank you just the same. I find myself wanting to find some way to block out the...glyphmon — 12:03 AM |
|
54C Complete Teardown/Rebuild
|
| Hello roy,
here is a link to the schematic .
Sincerely Richardradiorich — 11:54 PM |
|
54C Complete Teardown/Rebuild
|
| Richard,
The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM |
|
Preliminary work on wife's Silvertone 2014
|
| Did an alignment today which was interesting. IF alignment went great, almost all was already spot-on. Adjusting on th...glyphmon — 11:35 PM |
|
54C Complete Teardown/Rebuild
|
| The main problem with adding a Bluetooth input is that this set lacks a traditional power transformer to isolate it from...radiorich — 11:19 PM |
|
Who's Online
|
There are currently 2431 online users. [Complete List]
» 1 Member(s) | 2430 Guest(s)
|
|
|
|
 
|
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
