Author: "Dr. Gerald N. Johnson" <geraldj@storm.weather.net>
Date: Sun, 09 Dec 2007 22:23:38 -0600
That would make it sound like OFF capacitance would be most important. Maybe the circuit needs to be expanded to have a series switch element and a shunt switch element rather than depending on just
As i happen to have an OMNI VI+, i would sure appreciate a point in the correct direction for a replacement to the noisy amp relay. Thank - you. Paul (N6MYA) _________________________________________
I've seen similar criticism in 1990s Technical Topics columns in RadCom. The 1N4007 does well on insertion loss, 2nd order IP and 3rd order IP but fails on isolation (worst case 35dB at 10m rather th
Author: "Dr. Gerald N. Johnson" <geraldj@storm.weather.net>
Date: Tue, 11 Dec 2007 09:29:33 -0600
But only if each diode was to get the full reverse voltage. Dividing the DC voltage between them may not decrease the coupling when the capacitance goes as the inverse voltage squared. Half voltage,
are relay Tell us a bit more about the type of amp you're trying to interface and your level of comfort with soldering/de-soldering a couple components inside the rig. I can guide you through this,
Actually I was thinking in terms of full reverse V across each diode. Just have to DC isolate each diode and provide the bias/reverse V separately for each one. No more complex that the shunt option
Well, i have a Heath HA-14 and i have an isolation relay between the rig and the amplifier. The relay in the amplifier is quite noisy, however when i'm not using the amp, the relay in the rig seems t
A number of methods might quieten a noisy relay. You might have to do some detective work to find out if the relay closing is being mechanically amplified by the chassis or panel upon which it mounts
Author: "Dr. Gerald N. Johnson" <geraldj@storm.weather.net>
Date: Tue, 11 Dec 2007 18:26:10 -0600
Hobby shops involved in RC models carry foam sheeting designed to isolate the receivers from engine vibration. Those should be pretty good at preventing relay noise from reaching the cabinet. Gasket
Thanks Jerry for a good suggestion on a ready source of vibration isolation material! Yes, there are so many gasket materials, that many would not be good for isolation. The RC receiver isolation pad
The secret to solving this problem is to have bad ears. Between the U.S. Army, motorcycles with poorly muffled exhaust systems, and target shooting even with good hearing protection, I am lucky to he
and the amplifier. The relay in the amplifier is quite noisy, however when i'm not using the amp, the relay in the rig seems to be quite loud. Since i have the isolation relay at the power supply to
With all of this, I still have concerns that the HA-14 amp will be "hot keyed"...... noisy relay or not. Hot keying an amp is rough on the amp relays and other components in the amp. I think this app
Good solution, but the extra circuitry required within an older non-TT amp to establish a keying loop is beyond the means of most users. The sampling of the Omni Six's "T" buss results in the closur