I was going to ask what did they get instead, a fixed mast or something internal, but found your post detailing it:

https://www.clublexus.com/forums/sc-...r-antenna.html

Maybe those rocker switches can be made to raise and lower the rear window (with printed antenna), like an old SUV.

 

Yes, that post explains the diversity antenna setup in SC300's and SC400's (and other Lexus models of the time which also had motorized antennas) very well. Apparently the Soarer wasn't deemed to need more than just the rear windscreen embedded antenna. It was a forward thinking design choice when the car first went on sale in 1991 but on our continent there are some very wide open roads and Toyota/Lexus wanted enhanced long distance radio reception on the AM and FM bands.

Something we also forget is that the stock head units would adjust the antenna height depending on the frequency that was being tuned into and/or depending on the head unit's interpretation of the strength of the tuned radio frequency. The factory head units would then in addition switch between the signals from the rear windscreen antenna and aerial antenna dynamically in order to get the best reception in the cabin possible.

It kind of sucks to not have any of those intelligent radio tuning functions working any longer when we switch to aftermarket head units but the reception is still good enough. In my SC I have both antenna wire inputs plugged into a simple "Y" splitter adapter that accounts for the two different size round plugs. My aftermarket head unit's radio circuitry gets both signal sources combined together for better or worse.

 

I was gonna say, ejector seat, but Wellsong beat me to it.

It may be a switch so you can opt for a 2JZ or a 1UZ. I

I would agree it is probably an alarm defeat for valet.

 

My first Toyota was a 1984 Cressida which had the motorized antenna. Driving on the freeway, a newspaper flew up in front of me and ended up wrapping around the mast and snapped it. Ugh.

I was able to buy a new, replacement mast (which has the nylon cable). Now, taking out the broken part and reinstalling the new mast in the motor assembly ended up being a learning experience. Little did I know at the time that the same motor assembly would make its way into the SC300/400.

When my son had the car for his 7 year stretch (2004-11), he had a mast failure and I offered to tackle the replacement project. The mast part was still a reasonable $20-30 cost; as I recall, you could purchase the entire mast/motor assembly unit but it was over $400. Having “practiced” the process on the ‘84 Cressida proved quite useful in repairing the SC. Having a working antenna mast on our SCs is a rare feature these days. Employing the switch is the best way to “save” it from damage as using an AM/FM channel is not often chosen for audio entertainment.

 

I too tackled the OEM mast replacement within my existing antenna motor unit when I first bought my SC. It was as you say, a learning experience. Toyota put that same unit or very minor variations of it into a lot of their vehicles.

I hardly ever listen to AM now but I do love the weirdness of trying to see if any obscure and bizarre AM stations exist when I'm traveling in the middle of nowhere. Usually there's little to care about but occasionally there's something neat for a while. FM I still use extensively but very selectively. College radio stations or really tiny low power grassroots FM stations with real DJs are the only music focused ones worth listening to... as they're similar to what internet radio stations have become today. In all of those cases you have a real person (usually) curating a bunch of tracks that they have selected for you to listen to. AM radio used to have that same appeal but now it's mostly there for emergency broadcasts and strange sounding sideband frequencies that the head unit can sometimes pick up.

Honestly I've been wanting to install a small shortwave receiver into my SC just because it has the mast. It will still be a minefield of hit and miss but I have always loved the appeal of discovering what obscure radio broadcasts are out there. Perhaps it's because I built a crystal radio kit when I was a kid or because I loved playing with rabbit ear antennas on old analog TV sets as a kid or because I thought old analog satellite dish receivers were cool a long time ago even when the video signal from a foreign territory was scrambled and only partly watchable/audible. Altogether analog radio frequency transmissions still fascinate me and that's a big reason I have kept my SC's ridiculously tall OEM motorized antenna functioning.