Re: poor/distorted tx audio
开云体育Telephone company line I-O transformers: Your comments below reminded me of setting up production and custom automated test equipment for high volume production of the transformers.? The were ferrite potcores, about an inch in diameter. They had a bi-filar wound line input side, an equipment side winding, and an extra monitoring winding. Each transformer had to be tested for 14 variables: For example, turn ratio between the windings, balances, winding resistances , frequency response, insertion loss, and a high pot test. All the test equipment ran on HP-IL with custom modules and DVMs.? We made thousands per week in Dominican Republic.? That was about 35 years ago. Bertho ? From: [email protected] <[email protected]> On Behalf Of wn4isx via groups.io
Sent: 14 February, 2025 16:33 To: [email protected] Subject: Re: [electronics101] poor/distorted tx audio ? On Fri, Feb 14, 2025 at 01:55 PM, Roy J. Tellason, Sr. wrote:
The winding are separate, one inside the other so it has shorter turns and a lower resistance, the other is outside and has longer turns so it has a higher resistance. This isn't theory, my Bell Systems 600:600 show the same effect and are labeled as 600 ohms and XYZ DC resistance, the other is 600 ohms and ABC resistance. The side label says the XYZ winding must face the central plant. I have 4 and they are probably 80+ years old and each weigh 4 or 5 pounds. They are packed away so the XYZ and ABC resistance. ? This data can be used as your friend, feed your output signal to the higher resistance and take your signal from the lower, this way the lower resistance is shielded to some degree by the outer winding and will >probably< pick up less stray noise. ? |
Bertho