Fisher-Price Long Distance 900MHz Monitor

I own the 800ft range version of this, which I am sure has little to no differences besides a slight increase in range. The base station unit is very small, very easy to place, very easy to setup and use in general, and has excellent audio pickup. My unit even has an amber colored LED based nightlight on top that you can switch on or off by a push. Nice!

The receiver unit somehow manages to impress me even more than the base. It's TINY, it runs on batteries or included AC adapter, has 5 LEDs to indicate intercepted audio level, and the speaker level and clarity does quite nicely. Also, it has a belt clip that comes off very easily if you don't want to use it.

The system has four 900mhz channels to choose from. I've only had this thing less than a day, so I can't yet verify the claims of distance nor can I attest to longevity of the units.

Two downsides I'd like to comment on, before I digress into what can be done to these devices to make them BETTER.

First, the base is corded... Meaning the adapter is hardwired to the unit. I don't like that, because I like to take my electronics to whole new levels for one, and for two, if the adapter dies... you don't just replace it... you find one that matches the voltage requirements and then you have to do some cutting and twisting of wire at the very least. That didn't impress me at all, but then after what I did to my base unit, it's a non issue anyway.

The second thing I don't really like is the receiver using AAA batteries. For one, AAA cells don't have NEARLY the lifespan of AA cells, and for two, I wish it used AA's because that's what almost all my stuff uses. I picked things to be this way on purpose - I like universiality. ;-) It wouldn't have been a tough thing for them to build it to use AA's, it would have had a much longer runtime, and it wouldn't have that badly increased the size of the already absolutely tiny receiver.

Now on to the fun stuff. I got this thing not to monitor children, for I have none, and not for chickens, for I have none of those either. I got this to MODIFY, whee hee! And for those of you who are interested, let me say this thing is EASILY modified. It took me less than two hours to open up the base, desolder the hardwired power adapter, and install an LM317 based 6.5 volt regulator circuit with a very common 5.5mm DC power jack. The whole operation went buttery smoothly, I must say, and now my base unit will accept anything from 5 - 15 volts with NO problems other thar than a little warmth and probably a little higher current drain. I now have a base unit that will run on any of the hordes of easily and cheaply available DC adapters (think thrift store or yard sale) and in point of fact runs brilliantly on a car cigarette lighter adapter and is running GREAT out on my porch at this very moment on a small four cell AA pack. CORDLESS, baby! I can now plant my base unit anywhere, even leave it outside on a regular basis with a little weatherproofing say from a plastic ziplock baggie or such as that. God do I wish I'd had one of these when I lived in the country in the hills of Tennessee... I could have used this to listen to the local wildlife from the comfort of the indoors whenever I liked. Anyways... distance testing comes tomorrow, I'll be running it on a stronger 6 cell pack for full range and distance testing it thoroughly.

Just in case some of you think this is a crazy useless idea... consider the applications:

Fully cordless operation on batteries, perfect for power outages or monitoring areas with no AC receptacles.

Easy replacement with any common center positive DC adapter with the proper polarity, plug type, and voltage range.

MUCH greater spread of potential uses, including easy monitoring of areas outside the home like porches, garages, barns, sheds, wildlife of the two or four legged variety... the list goes on and on. I plan to modify another and keep one for whatever use comes along, and the other will likely be placed permanently in my car to monitor it against breakin or vandalism when I am home and not watching it (who has the time to waste on watching their car, even in a rough neigborhood?). The second I hear any suspicious noises over the receiver, I can go to my window to see what's up. Paranoid? Not at all... last spring I discovered that my car was being used as a worktable by some people that were moving out and didn't care what they did around here anymore.

One could even use a pair of these as a type of intercom between two areas, exploiting the four channels to create a full duplex audio link. The more I think it over, the more ideas I get. :-)

Anyway... bottom line is these are GREAT little room monitors, and have great potential with a little hacking. Very affordable, very easy to use, and great features, and so far great reception. They have my vote.

UPDATE:

It's now been 11 days since I bought this thing and modified it, and now I know a LOT more about them, and have more deeply modified both the base and receiver.

1) The receiver unit has inside it a tiny potentiometer for squelch adjustment. I found that my receiver was prone to cutting off when there was still plenty of signal to be had, IE, I could get more range. SO, I set my squelch adjustment to completely OFF. No more annoying "BEEEP BEEEP" even when signal is GONE, and if you're willing to put up with a bit of static, you can get a LOT more distance.

2) I increased the transmit power by adding a very simple PN5179 transistor RF amplifier between the antenna output and the antenna itself. I have probably gained about .1 - .25 watt, enough to be quite noticeable, and harmonic output is still very low. Bear in mind this no doubt violates FCC regs, so do this at your own risk or not at all.

3) I did fairly extensive distance testing both before the power increase and after, and have found this unit to perform quite impressively especially in open air conditions. During my field tests BEFORE the power boost, I placed the transmitter on the passenger seat of my car and went walking with an AOR8200 MKII scanner, and found excellent reception in excess of 200 feet (that's through car sheet steel, mind you), and after the power modification I found excellent reception as far away as 300 - 400 feet with the exact same environment and positioning of car and transmitter. If I am indeed to expect 800ft of distance from the stock transmitter, which I believe, then this modification should be getting me as much as 1600ft in the open air. I have not tested this, but I have reason to believe it is true.

4) I have since tested the base unit on various power sources, from a four pack of AA NiMH cells to an 8 pack of AA NiMH cells, as well as 12VDC from AC adapters and my car cigarette lighter socket, and have found only the four-AA pack to be wanting, as it only provides 5VDC or just over, and the base now uses 6.5VDC. Temperature inside the case seems to be more than reasonably low, and current drain appears to be less than 50mA no matter how I power it.

5) Before the squelch adjustment, I had sporadic losses of signal and difficulty at times in reaquiring signal once lost. After the squelch mod, needless to say, it never cuts out and I have had NO problems of any kind with either the base or the receiver.

6) Inside the base unit is a tiny potentiometer that adjusts the microphone level. I was surprised to find that it was set near middle and had MUCH more available gain if I so chose to set it that way. It's my feeling that the stock setting is already a little hot, so I didn't increase it but a hair to make it more suitable to use for detection of subtle noises, for security type situations and the like. In a very noisy environment, I believe this pot could be set much lower for much better clarity in the received audio, although I have not yet tested this theory.

Have fun! :-)

NR

I found this monitor to be a very good value. It is a good monitor and I would recommend it for naps, because the senisitivity and reception are very very good and you are awake and the white noise is not annoying when you are awake. But the white noise, or fuzz, or whatever you call it is still there (like every monitor I have ever had)even when the baby's room is perfectly quiet. I personally hate that. I want a monitor that is perfectly quiet without any fuzz because I don't like sleeping to the white noise/fuzz even if it is soft. The range is very good, the sensitivity is very good, no problems with interference with our phone or wireless networks or neighbors, It has low white noise compared to other monitors, and the night light is an unexpected bonus. I wish I could buy a second receiver, and I wish it had no white noise.

I got the Fisher-Price monitor for a little different reason, my cats. I built an enclosure for them, but my Russian Blue has such a soft voice I could never hear her when she wanted to come back in. The Fisher Price monitor works perfectly for what I need it for. It picks up everything. I can unplug the receiver and take it to any room in the house and still have a strong signal. Now I never miss a call when I'm being summoned. Good monitor, great price.

The monitor is great because there are lights that blink to let you know there is sound coming from the baby's room even if the volume is turned down. I've cooked outside on the grill while the baby has been sleeping inside on the 2nd floor and could hear if she rolled over. Very happy with my purchase!

I bought this from Target yesterday. All I get is a flashing green light and beeping - LOUD beeping from the receiver that was so loud it woke up my son from the next room with the door closed. That's supposed to indicate that it's out of range, but like I said, I was in the next room. Everything was plugged in and set up correctly, and the channels matched. I can't get it to work from anywhere in the house. Maybe I just got a lemon, who knows? I hope that's the case.