Toy walkie talkie - teardown, range test and look inside - Page 1
Forum section: electronics / general

author: vk3yedotcom
author_rank: Frequent Contributor
timestamp: July 18, 2012, 09:17:21 pm
content: [when seeing these things in the shop, you know they're going to be rubbish, but curiousity is too strong to not buy and try]This video compares 2012 walkie talkies (<$8 for 2) with 1982 vintage walkie talkies ($9.95 ea) similar to which many here would have had as a kid.Superficially both are similar - 4 or 5 transistors - AM transmitter - super regenerative receiver.However the performance and stability of them is very different as you'll see when I take them out. I'll also look inside and see that early 1980s style circuit boards are still alive and well in low end toys.And what happens when you put two radiating superregen receivers together? They scream! See this and more in the video below:Peter

author: RCMR
author_rank: Frequent Contributor
timestamp: July 19, 2012, 12:55:04 am
content: I noticed that when you were rang-testing the purple terror toys, you not only had the receiver antenna horizontally polarized while the transmitter antenna was vertical (big losses) but you also had the receiver antenna pointed directly at the transmitter -- more big losses assuming a toroidal or near-toroidal radiation pattern.It would be interesting to see if vertically orienting both antennas had an improvement in range -- I would expect at least a doubling in real-world terms - perhaps more (or not -- given that the antennas are not quarter-wave and probably totally mis-matched to the transmitter/receiver circuitry).

author: vk6zgo
author_rank: Super Contributor
timestamp: July 19, 2012, 02:22:09 am
content: Hi Peter,That takes me back to when the kids were young & we were in Quairading.I told them I was going to get them a couple of "walkie talkies",but when I showed them the DSE ones,they weren't impressed-----apparently they were too plain looking!Anyway,I bought some other type,but it was very similar inside.They had a ball,running around with their mates,talking on those things.I kept track of them with a Drake SSR1,just using the built-in whip antenna.The range was similar to the DSE one you tested,so when they started to fade out,it was time to go & round them up!Not that they could get into much trouble in a country town in those days!ABW2 & TVW7 Transmitter sites had 27MHz handhelds,mainly for when you were up the tower,but we used them elsewhere as well.Both sets were identical units & dated from the early '60s.They were a far more serious radio,& I remember using them over several km on occasion.

author: vk3yedotcom
author_rank: Frequent Contributor
timestamp: July 19, 2012, 08:54:12 am
content: Terror toys? I like it! To answer the question, I managed to prop it up to make the antenna vertical and the range was still pathetically low.I suspect one problem is poor receive sensitivity - though superregens are normally pretty sensitive the one in these units didn't hear the strong crud on 40.66 that the FT817 picked up.@vk6zgo - in their time the DSE ones were pretty basic. They didn't have Morse code, and neither did they have a volume control to turn that hissing down (unlike others). So you couldn't very well play hide and seek with one!