I am about to have a second baby.  I want to continue to use my
current 900 MHz monitor with my daughter and purchase a second monitor
for the new baby.  My understanding is that as the second monitor is
not on a frequency of 900 MHz then it will not interfere with the
current monitory.  I need to verify that this is the case and also to
find a RELIABLE (i.e. well reviewed) monitor that is not 900 MHz.  I
would not want to spend more than $60 if possible and do not need
video or anything special.  Just a sound monitor.

First of all, congratulations on the second baby! It's never too soon
to be planning ahead, so I hope that this answer will help you.

To answer your question about non-900 MHz baby monitors, they are
harder to come by these days. But it still is possible to find
monitors that use the 49 MHz band, which usually offer shorter range
because of FCC-imposed power restrictions. But unless you live in a
mansion or you plan to listen from far outside the house, they should
be than sufficient. Almost all of them cost less than $60.

Generally speaking, any baby monitor that doesn't advertise itself as
being on the 900 MHz band or 2.4 GHz band is designed for use on the
49 MHz band.  (The 2.4 GHZ models are the newest kind, but they're
more expensive than what you're looking for and usually include
video.)

Here are retail pages for some monitors that use the 49 MHz band.

Fisher-Price Sound 'n Lights at Amazon.com
http://www.amazon.com/exec/obidos/ASIN/B00005QJ02/

Safety 1st Secure Starlight Monitor at Wal-Mart
http://www.walmart.com/catalog/product.gsp?product_id=2031964

Safety 1st Clear Connection at Epinions.com
http://www.epinions.com/kifm-B-BEquip-Nursery-Monitors-Safety_1st_Clear_Connection

Evenflo Constant Care at Babyant.com
http://www.babyant.com/bn015043.html

OPP Soundsleep Monitor at BabyMajesty
http://www.babymajesty.com/viewproduct.asp?x=9504&z=65&title=OPP%20SoundSleep%AE%20Monitor%20-by-Graco

The Fisher-Price monitors seem to get consistently positive reviews.
You can find reviews of monitors here:

Epinions.com
http://www.epinions.com/kifm-Nursery-Monitors-All

Epinions.com reviews of Fisher-Price monitors
http://www.epinions.com/kifm-Nursery-Monitors-All-Fisher_Price

Consumer Search
http://www.consumersearch.com/www/family/baby_monitors/

Reviews of Baby Monitors
http://www.bestbabyproducts.com/monitor.html

As to your question about whether you can use two 900 MHz baby
monitors in the same home, the best answer I can give you is that you
have to try it to find out whether two particular monitors will
interfere with each other.  They might, and they might not.  If
they're of different brands, they very well may use different channels
and not interfere with each other (just as two adjacent TV channels
don't interfere with each other).

There are literally dozens of channels available in the 900 MHz band,
so it wouldn't be surprising if two monitors don't conflict with each
other.  Some units also use something known as spread spectrum, in
which the channels rapidly change in an arbitrary fashion as a way of
reducing interference. Also, some 900 MHz units use digital modulation
and some use frequency modulation, and in that case there may limited
interference.

Keep in mind also that many cordless phones use the 900 MHz band, so
it's possible that a phone and a baby monitor could interfere with
each other, especially if they're using the same or adjacent channels.
(Some cordless phones change channels each time you use them, or look
for a vacant channel before picking one.)  You also can get
interference from baby monitors or cordless phones in homes nearby.
(To complicate matters, some of the newer 2.4 GHz baby monitors can
have conflicts with wireless computer networks using the same band.)

So that takes us back to what I said earlier: The only way to really
tell if one 900 MHz baby monitor will interfere with another one (or
with a 900 MHz cordless phone) is to try it and find out.  But if you
use one 900 MHz monitor and one 49 MHz monitor, you don't need to
worry (although keep in mind that some cordless phones, especially
older ones, also operate in the 49 MHz band).

Most of this information on interference has been based on personal
experience and from my knowledge as a licensed ham radio operator. You
can get an overview of wireless devices (a baby monitor isn't
electronically all that much different than a wireless phone, except
that you don't have a transmitter and receiver in the same unit) on
the following page and by following the links on it:

What does 900 MHz mean in a cordless phone?
http://www.howstuffworks.com/question320.htm

I hope this hasn't been too confusing. Baby monitors and cordless
phones usually don't face serious problems from interference, but it's
difficult to make guarantees without having the technical data for the
precise models being used both by the consumer and by the consumer's
nearby neighbors.

Best wishes, and please ask for clarification if I've been too
confusing in providing this technical information.

Sincerely,

Mvguy-ga







Google search terms:

reviews "baby monitors"
://www.google.com/search?hl=es&ie=UTF-8&oe=utf-8&q=reviews+%22baby+monitors%22&btnG=B%C3%BAsqueda+en+Google

"49 mhz" "baby monitors"
://www.google.com/search?hl=es&ie=UTF-8&oe=utf-8&q=%2249+mhz%22+%22baby+monitors%22&btnG=B%C3%BAsqueda+en+Google

Thank you!  I was researching monitors on epinions but I didn't
realize if they didn't SAY 900 MHz then they were 49.  That was what
was confusing me the most.  Our cordless phones don't bother our 900
MHz monitor so I'm not worried about the 49.  Thanks for a great
answer!

Greetings Melbalicious:

I phoned GracoBaby on your behalf and spoke with a nice gentleman
named Andy.  I asked him about your MHz concern and he said "In this
case, it's the luck of the draw" and went on to explain that sometimes
another MHz will work and sometimes they won't.  He suggested you try
a model and see.  He added that mobile phones can sometimes interfere
with static, too, and that even a neighbor's phone can cause some
units to respond poorly.

"Graco Customer Support is available Monday through Friday, 8am to 5pm
EST.
800-345-4109 (US)"
From http://www.gracobaby.com/customerservice/contact_us.aspx

You might consider upgrading to a set like the Graco Ultra Clear
Monitor with 2 receivers - see
http://www.epinions.com/Graco_UltraClear_Monitor__2_receivers_ for the
specs and price (the price is within your suggested range).  There are
also 2 reviews of the product there:

Graco Ultra Clear -- Jimi would be proud [rated the product with 4
stars]
http://www.epinions.com/content_46049300100

Listen to this... [rated the product with highest rating, 5 stars]
http://www.epinions.com/content_43508469380

I would like to have posted my findings as an answer but you stated "I
want to continue to use my current 900 MHz monitor" and my answer is
instead suggesting replacing it with a 2 receiver model.

Best regards,
journalist-ga


SEARCH STRATEGY:

"baby monitor" compatibility
"baby monitor" review compatibility
"baby monitor" reviews
"baby monitor" 2 receivers

Thanks journalist.  The problem is that the children will be in two
separate rooms so two receivers really doesn't help me.  Thank you for
your efforts.

I had worked for a company called RF-Link who is one of the first
company who makes these wireless monitor system, so I am pretty
familiar with these systems.  Usually 2.4Ghz systems are better than
900MHz systems because 900MHz is a very crowded band, it gets
interference easily.  In the market now, 900MHz are mostly more low
end products.  If you want to monitor 2 locations at the same time. 
You can get an extra camera and monitor them at the same monitor.  I
had been selling a 2.4GHz model (and all accessory)for quite some time
and I believe it is the best system out there.  Plus I am selling them
at very low price because I got them straight from the factories. 
Almost all customers are very satified with it.  If you are intersted,
you can log on to: www.coolgadgets.net or go to my ebay auction(user
ID: v888).  If you have more questions, you can also contact me.