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[email protected] sidwelle@gmail.com is offline
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Default TV/FM antenna pre-amp location.

Does anyone see an issue with mounting a pre-amp for a attic mounted antenna in attic with the antenna ?

Will the attic heat cook the pre-amp ?

Thanks
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David Platt David Platt is offline
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Default TV/FM antenna pre-amp location.

Does anyone see an issue with mounting a pre-amp for a attic mounted antenna in
attic with the antenna ?

Will the attic heat cook the pre-amp ?

Thanks


I design such equipment, and we life test it for a month at 85C. It
has to meet spec all through that - and down to -40C. It'll be ok


I'd expect that there may be somewhat reduced long-term reliability
due to the heat... continued high operating temperatures are
notoriously bad for electrolytic capacitors. A preamp designed for
commercial-grade service, and built with high-quality 105C capacitors
would probably be less subject to trouble than designed-to-be-built-
cheaply consumer-grade junk. You often get what you pay for :-)

Some of those cheap "mount on the mast" preamps and "active antenna"
systems have caused real problems in the past. There was an incident
a few years ago in which one or two of these were installed on boats
moored in a harbor here in Northern California. Under certain
conditions they'd "go unstable" and break into spurious oscillation
(always a risk for any amplifier) and they were squealing enough UHF
noise back out through the antennas to saturate and blank out GPS
receivers located within a mile or so of their location. This is a
Very Bad Thing for captains who are trying to enter a fog-bound harbor
safely!




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Don Pearce[_3_] Don Pearce[_3_] is offline
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Default TV/FM antenna pre-amp location.

On Fri, 5 Jul 2013 10:44:26 -0700, (David
Platt) wrote:

Does anyone see an issue with mounting a pre-amp for a attic mounted antenna in

attic with the antenna ?

Will the attic heat cook the pre-amp ?

Thanks


I design such equipment, and we life test it for a month at 85C. It
has to meet spec all through that - and down to -40C. It'll be ok


I'd expect that there may be somewhat reduced long-term reliability
due to the heat... continued high operating temperatures are
notoriously bad for electrolytic capacitors. A preamp designed for
commercial-grade service, and built with high-quality 105C capacitors
would probably be less subject to trouble than designed-to-be-built-
cheaply consumer-grade junk. You often get what you pay for :-)

Some of those cheap "mount on the mast" preamps and "active antenna"
systems have caused real problems in the past. There was an incident
a few years ago in which one or two of these were installed on boats
moored in a harbor here in Northern California. Under certain
conditions they'd "go unstable" and break into spurious oscillation
(always a risk for any amplifier) and they were squealing enough UHF
noise back out through the antennas to saturate and blank out GPS
receivers located within a mile or so of their location. This is a
Very Bad Thing for captains who are trying to enter a fog-bound harbor
safely!




There are equations for calculating electrolytic longevity. They use
ripple current, voltage and temperature. 30 years minimum is the spec
I work to. In practice, they last a lot longer

d
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[email protected] sidwelle@gmail.com is offline
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Default TV/FM antenna pre-amp location.

On Friday, July 5, 2013 11:34:58 AM UTC-5, wrote:
Does anyone see an issue with mounting a pre-amp for a attic mounted antenna in attic with the antenna ? Will the attic heat cook the pre-amp ? Thanks


I was just concerned with creating a file hazard. If you feel that this is a non issue, thin I will install.

I ordered: Antennacraft 10G222.
The specs stated that it had good gain and zero insertion loss w/separate inputs for VHF and UHF.

Any opinion on the unit ?

Thanks



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[email protected] sidwelle@gmail.com is offline
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Default TV/FM antenna pre-amp location.

On Friday, July 5, 2013 11:34:58 AM UTC-5, wrote:
Does anyone see an issue with mounting a pre-amp for a attic mounted antenna in attic with the antenna ? Will the attic heat cook the pre-amp ? Thanks


At the time I placed the order, my thought was more is better.

I take it this is not one of the units you designed or tested ?
No thoughts on it overheating ?

Thanks
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Trevor Trevor is offline
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Default TV/FM antenna pre-amp location.


wrote in message
...
On Friday, July 5, 2013 11:34:58 AM UTC-5, wrote:
Does anyone see an issue with mounting a pre-amp for a attic mounted
antenna in attic with the antenna ? Will the attic heat cook the pre-amp
? Thanks


I was just concerned with creating a file hazard. If you feel that this
is a non issue, thin I will install.

I ordered: Antennacraft 10G222.
The specs stated that it had good gain and zero insertion loss w/separate
inputs for VHF and UHF.

Any opinion on the unit ?


If you are in a capital city you won't need UHF after the restack. You
*won't* want it in fact so the new LTE (digital bonus) spectrum doesn't
create interference.

Trevor.


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Trevor Trevor is offline
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Default TV/FM antenna pre-amp location.


wrote in message
...
On Friday, July 5, 2013 11:34:58 AM UTC-5, wrote:
Does anyone see an issue with mounting a pre-amp for a attic mounted
antenna in attic with the antenna ?

At the time I placed the order, my thought was more is better.


Not with digital, too much signal is just as bad as too little. Of course
too much signal can overload some analog inputs as well.

Trevor.




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Trevor Trevor is offline
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Default TV/FM antenna pre-amp location.


"Trevor" wrote in message
...
wrote in message
...
On Friday, July 5, 2013 11:34:58 AM UTC-5, wrote:
Does anyone see an issue with mounting a pre-amp for a attic mounted
antenna in attic with the antenna ? Will the attic heat cook the pre-amp
? Thanks


I was just concerned with creating a file hazard. If you feel that this
is a non issue, thin I will install.

I ordered: Antennacraft 10G222.
The specs stated that it had good gain and zero insertion loss w/separate
inputs for VHF and UHF.

Any opinion on the unit ?


If you are in a capital city you won't need UHF after the restack. You
*won't* want it in fact so the new LTE (digital bonus) spectrum doesn't
create interference.


Whoops, may not apply to you, depending on country! :-)

Trevor.


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Kevin McMurtrie[_3_] Kevin McMurtrie[_3_] is offline
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Default TV/FM antenna pre-amp location.

In article ,
(David Platt) wrote:

Does anyone see an issue with mounting a pre-amp for a attic mounted
antenna in

attic with the antenna ?

Will the attic heat cook the pre-amp ?

Thanks


I design such equipment, and we life test it for a month at 85C. It
has to meet spec all through that - and down to -40C. It'll be ok


I'd expect that there may be somewhat reduced long-term reliability
due to the heat... continued high operating temperatures are
notoriously bad for electrolytic capacitors. A preamp designed for
commercial-grade service, and built with high-quality 105C capacitors
would probably be less subject to trouble than designed-to-be-built-
cheaply consumer-grade junk. You often get what you pay for :-)

Some of those cheap "mount on the mast" preamps and "active antenna"
systems have caused real problems in the past. There was an incident
a few years ago in which one or two of these were installed on boats
moored in a harbor here in Northern California. Under certain
conditions they'd "go unstable" and break into spurious oscillation
(always a risk for any amplifier) and they were squealing enough UHF
noise back out through the antennas to saturate and blank out GPS
receivers located within a mile or so of their location. This is a
Very Bad Thing for captains who are trying to enter a fog-bound harbor
safely!


Ceramics are in the hundreds of microfarads now so electrolytic caps are
becoming rare except for line power rectification. Ceramics are
smaller, more reliable, handle more current, and don't need special
soldering. There are even ceramic capacitors with resistive dampening
to prevent ringing.
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