And you thought your 40 year old Spragues Atomlytics were bad
http://www.freerepublic.com/focus/f-news/849190/posts
I was looking up info on some Teapo caps. Specifically, I have a bunch of 100uf
@ 450 WVDC and am hoping to use them for filters. While doing a search I came
across the above a
Hi Dave,Sorry
that I can't help you guys. I am in MI now, (that's what happens when you
marry a MI girl)
I used to work AM back in the 80'S. Had trouble finding stations to
talk to. Didn't have trouble causing tvi. Used a Johnson
I feel there must be some other thing that is overlooked about the connector
or cable. 15 ft of cable would not normally cause any noticeable effect on
audio unless the terminating Z was greater that a few mega ohms as it would
be for some of the older equipment made for Xtal mike input but I can'
Most RF coax cable has a capacitance anywhere from 26 to 30 pf per foot.
So if you had 15 feet of cable you had about 390 to 450 pf of parallel
capacitance.
The preamp output and amp input may be higher impedance than you
realize. If you are feeding the output from the plate of the preamp it
The mike preamp is a berringer ultra voice, 600 ohm output I thought,
its balanced, I unbalance it at the output (berringer says this is ok), and
it goes to the input of a 120 watt per channel audio amp, it actually
feeds both channels so I have 4 outputs right and left, a and b.
I have no documen
I know the D104 is very sensitive to the cable used, on mine,
only the cable that came with the mike works well at all.
This was on a line level link between the output of the mike
preamp and the power amp, lowish impedance I thought.
I measured the capacitance of the cable and got something like
The characteristic impedance of the cable is of little importance at
audio frequencies. It is the capacitance that matters. If the circuit is
a low impedance one then the capacitance does not matter much either.
But in a high impedance circuit the capacitance becomes important.
73
Gary K4FMX
Coax cable will have a certain amount of capacitance per ft. which if
terminated to a high Z load in the speech equipment will result in a loss of
high freq audio. If how ever the line is terminated with the characteristic
Z of the line then it can be very long. This works ok for very low Z
micro
Gentlemen,
Most guys think that using the RF cable is good for eliminating RF
feedback into the input audio system. True, but a better way if your
using high impedance line (low capacity type) is to add a second braid
on the outside of the audio cable for RF reduction. The low dielectric
constant o
50 ohms is 50 ohms, plus 20 pf per foot cap all are killers! Mike,K4XM
- Original Message -
Subject: Re: [AMRadio] RE: r390a, sx17, t4xb for sale
>>> > I have had a few reports of my audio not having a lot of highs,
> > even though I boost the mid and upper voice frequencies.
> > There i
High capacitance per foot on the cable. In the high impedance mike
circuit a little capacitance will kill the highs.
73
Gary K4FMX
Brett Gazdzinski wrote:
The R390a is sold, Bob (wa3gfz) jumped on this one and picked it up
last night!
I have had that R390a for about 20 years, and its been w
The R390a is sold, Bob (wa3gfz) jumped on this one and picked it up
last night!
I have had that R390a for about 20 years, and its been working fine
for the last 15 years at least, after a rash of broken gear clamps
the first couple of years I had it.
I hope Bob has as good a performance from it as
Greetings all,
Still looking for Montana to complete WAS on 75M AM. If someone can
help, I will look for you at the time and frequency of your choosing.
In several years of AM activity on 75M, I've yet to hear any of you
folks out in the Big Sky country.
73 de Dave, W4QCU
Oak Ridge, TN
13 matches
Mail list logo
