Curse of the Yellow Dot - Page 1
Forum section: electronics / rf-microwave

author: hpssb
author_rank: Contributor
timestamp: August 30, 2024, 02:07:09 pm
content: Quick post here after a few queries along the lines of "why do come radio repairs cost so much more and take so much longer than others". With 27 meg SSB radios, the first thing we always ask when we get an email query about the approximate cost / timeframe of a repair is:Is there a yellow dot sticker on the rear panel of the radio?This throws a lot of people, especially those what weren't living in Adelaide in the late 90's / early 2000's.For those that were, the go-to man for modifications to increase channels / power / modulation / receive performance / things that make beeping noises was the "Yellow dot man". He would fit extra parts to the radios to achieve those goals, so he must have had some kind of idea what he was doing, but the standard of workmanship was on the "sub prime" side, something along the lines of the EEVblog #822 World's Worst Tablet Computer video on Youtube. Undoing these "improvements" and putting the radio back to factory condition can take months as a spare time job and would be completely uneconomic if I wasn't semi-retired and still charging commercial labor rates. I've never met or spoken to Mr Y.D. but only know his handiwork from ham/cb gear we've had sent in here for repair.His "signature" was one or two yellow dot stickers attached to the rear panel of the radio.Received two identical radios today, Hatadi Pearce Simpson Cheetah Mk1 units, mid 80's vintage, made by Uniden, and selling in clean condition for $300+, closer to $400 in unworn condition with the box and original accessories, so worth spending an hour or two on. They usually only need some bad electrolytics replacing and a squirt of deoxit in the controls and they are good for another 20 rears.These were from a deceased estate and the son wanted them repaired / returned to standard, so with the sentimental value was prepared to pay a bit more than the economic cost. One radio was untouched, probably in case of a visit from an ACMA inspector, and the other had the dreaded yellow dot on the back. Uh-oh....Rear panel of the "improved" radioStuff added to the modified radio. All this added junk has to go. The whole lot was secured with hot snot glue.Channel switch butchery. Shaft was bent and made to hit two microswitches for up/down. The whole lot was held together with hot snot.Part of the front panel board (where the original channel selector was) had been cut out to make room for the modified channel selectorThe removed half of the front panel board was then hot snotted to the main board a few inches away from where it originally wasClose up of top of added board. IC part numbers dremelled off so nobody would copy this masterpieceClose up of bottom of added board. Wired up with old PATA grey ribbon cable separated into individual wires.Extra board regulator soldered directly to chassisThe channel display would only light up when the antenna was connected, had me mystified for a while. Then I realised it's a floating chassis so it can be used in positive earth trucks / boats without DC corrosion issues. Our workshop antenna (and the dummy load / load selector switch) is earthed via a lightning arrestor. So the regulator common was connected only via the antenna groundAdded connections to the radios synthesizer / PLL circuitry, probably for "extra" channelsWhat it should look like - top of the unmodified radioWhat it should look like - bottom of the unmodified radio after repair. The old grey electrolytic capacitors were just replaced with new red Wurth components and the radio works like new.Big difference between these two. First one will be here for a few months as a part time project. The second one was stripped, repaired, cleaned, and aligned in 90 minutes - and on its way back to the owner...Edit: fixed minor typos...

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 30, 2024, 02:15:32 pm
content: Wowie, what a piece of work! Does the son know what this looks like? Seems to me it might have more sentimental value framed on the wall than in any kind of operating condition (please, seriously, keep that thing off the air as-is)...(But I guess the implication is that someone else did the work and the deceased merely got the work done?)Tim

author: hpssb
author_rank: Contributor
timestamp: August 30, 2024, 02:46:38 pm
content: The son is a local diesel mechanic who sent the radios to us. His father - an avid CB/ ham/shortwave buff passed away earlier this year and the son sent the two radios to us for repair / restoration.The father had the one radio modded about 25 years ago, the modified one stopped working a year or so later and the modifier man was uncontactable, so it sat in a cupboard from about the rear 2000 and was found after he passed. Summers here in Oz are 40 degrees C / 104 degrees F regularly so the radio likely failed when the hot melt glue holding it all together started to melt.He's been told it'll be an expensive fix, he's OK with that. It will be clean when it's fixed, in the meantime it will be dummy load only...

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: August 30, 2024, 03:10:43 pm
content: It is nice to hear and see that the compulsion of butchering perfectly good radios is not confined to just the US.CBers seem to have spread this disease around the world.

author: hpssb
author_rank: Contributor
timestamp: August 30, 2024, 03:35:26 pm
content: It's alive and kicking here in Oz, and has been for the 30 years we've been open for (and probably even longer than that)...

author: CaptDon
author_rank: Super Contributor
timestamp: August 31, 2024, 12:20:58 am
content: What a hacker Mr. yellow dot is!! That is some of the worst aftermarket work imaginable!! All that to go 'out of band'. In the U.S. they already have 40 channels that almost no one uses anyway. It amazes me how the U.S. a$$holes want to talk 'skip' on channel 19 which was the truckers "Break for some local information channel" placed there when the original trucker's Ch10 was causing to much interference with the Ch9 REACT Emergency Channel. OF course it earned the nickname 'Childrens Band'. Back in the 6 channel crystal controlled days we would switch the receive and transmit crystals. The radio may have put out a tad less power and the receiver a tad less sensitive, but it worked like a charm and we were on 'our own' channels with zero interference from undesirables!!! Yes, it was illegal and yes back then I was only 30 miles from an F.C.C. field office but we weren't running illegal power levels and no one ever paid us a visit. I even had my ham novice ticket at the same time!! I am one of the dinosaurs still holding an advanced ticket at the moment. 2 X 2 call is a dead give away!!