The Fisher 440-T FM Receiver
Posts: 16,507
Threads: 572
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
Today's DMM will give you a true RMS reading (my Fluke 87 is good up to 200kHz) so what you could do is feed a signal and at the same time measure it with a DMM, then set the signal to peak exactly at say full screen with even number of division p-p, read the DMM and multiply it by 2.828 (2x1.414) and then divide it by the number of the divisions you have p-p, this will be your V/div.
As for the Horz - you will need a counter, then - same thing, a known frequency and qty of periods per div (make it even).
As for the input signals, it is always better to test an amp with a real audio oscillator with adjustable amplitude. You should know what your input max at the full power is, then set it, feed it in and then see at what level of volume if any you distort.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Messages In This Thread
RE: The Fisher 440-T FM Receiver - by morzh - 03-04-2015, 02:44 PM
Users browsing this thread: 1 Guest(s)
|
|
Recent Posts
|
|
PT 6 chassis screws size???
|
| Hello bridKarl,
that sounds right or maybe 8/32 .
Sincerely Richardradiorich — 01:00 AM |
|
PT 6 chassis screws size???
|
| Have this done except for missing chassis screws.
It looks like 1 inch 6/32 sheet metal screw may work but can anyone s...bridkarl — 10:32 PM |
|
Philco model 38 code 121 not receiving signal.
|
| Hello Stormlord,
Well done on rewinding that coil it turned fairly good for your first one.
Sincerely Richardradiorich — 09:12 PM |
|
Philco model 38 code 121 not receiving signal.
|
| Well here it is. It ain't pretty, but hopefully it'll work.
I checked it with my DMM on continuity and it keeps and r...Stormlord5500 — 08:56 PM |
|
Philco 42-345 Restoration/Repair
|
| Yes, 57 is an electrolytic cap that should be 12 mfd 400 volts according to the parts list from the Phorum library schem...RodB — 06:01 PM |
|
Philco 42-345 Restoration/Repair
|
| Looks like if I am reading it correctly it looks like the silver capacitor#57 that appears to be a replacement is of a l...osanders0311 — 05:09 PM |
|
Philco model 38 code 121 not receiving signal.
|
| Thanks Arran. Yeah this plastic is pretty thin. It's a little thinner than the original stuff. It kinda reminds me of p...Stormlord5500 — 04:37 PM |
|
Testing a speaker and output transformer Trutone A2-G
|
| The equivalent of one short turn is basically the same as that of a shorted load.
If it is the primary's turn, then the ...morzh — 03:53 PM |
|
Testing a speaker and output transformer Trutone A2-G
|
| I've never had an output transformer become shorted, the failure mode is usually an open primary, or in a center tapped ...Arran — 03:52 PM |
|
Philco model 38 code 121 not receiving signal.
|
| As long as the plastic sheeting isn't too thick, I think that the thickness of photographic film would be just about rig...Arran — 03:19 PM |
|
Who's Online
|
| There are currently no members online. |
|
 
|
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
