View Full Version : Sylvania Dualette resto.


Electronic M
05-21-2017, 01:48 PM
Anyone else here ever wondered what is inside a Dualette? :D

https://c1.staticflickr.com/5/4246/34656893501_13ce275bcc_z.jpg (https://flic.kr/p/UNvD1z)

I finally had some bench time yesterday, and decided I wanted to start by giving this a turn on the variac. It came up with a loud hum in the audio and a raster with a lot of spacing between each scanline....However that raster was only visible while turning the brightness knob.

Pulling the back and checking the CRT revealed a rather healthy CRT and that most of the tubes are original Sylvania. Also many of the paper caps on the main board were replaced by Sprague labeled yellow film caps similar to the yellow film caps commonly used by the radio community in restos presently.

https://c1.staticflickr.com/5/4274/33947201904_7a2c5d6666_z.jpg (https://flic.kr/p/THNhqy)https://c1.staticflickr.com/5/4172/34627288142_3a736ec1fa_z.jpg (https://flic.kr/p/UKTUnm)https://c1.staticflickr.com/5/4177/34749474996_8fbfa0352c_z.jpg (https://flic.kr/p/UWG9gf)https://c1.staticflickr.com/5/4221/33947182414_efb5216f22_z.jpg (https://flic.kr/p/THNbCw)https://c1.staticflickr.com/5/4168/33980532043_9670bcb3a6_z.jpg (https://flic.kr/p/TLK7j8)

As I figured, an afternoon recap session was all it needed to bring it back to life. I did leave one 2uF 50V lytic in the sound, but it does not seem to be adversely affecting anything. The recap was fairly straight forward, though some caps on the main board needed the vert out trans unmounted to get at them and a few caps on the board had their traces partially blocked by the mounting frame rails making access without removing the board tricky. The sweep section of the chassis is also a bit cramped to recap, but would have been easier if I had warmed up a smaller iron.

https://c1.staticflickr.com/5/4204/34789643445_2854eae139_z.jpg (https://flic.kr/p/V1f1WH) https://c1.staticflickr.com/5/4200/33980497843_4a7fc7e57f_z.jpg (https://flic.kr/p/TLJW9t) https://c1.staticflickr.com/5/4200/33947161364_f454bd8c69_z.jpg (https://flic.kr/p/THN5nA)https://c1.staticflickr.com/5/4175/34789658795_0dedd5ddd1_z.jpg (https://flic.kr/p/V1f6vn)https://c1.staticflickr.com/5/4270/33980517623_c4fcd02401_z.jpg (https://flic.kr/p/TLK32v)https://c1.staticflickr.com/5/4223/33980521513_1110b8ef08_z.jpg (https://flic.kr/p/TLK4bz)https://c1.staticflickr.com/5/4245/34627269052_b195632771_z.jpg (https://flic.kr/p/UKTNGd)

Post recap I took it completely apart, hosed the dirt out, cleaned the safety glass/CRT face, and scrubbed the cabinet. Once it drys enough to power up again I'll adjust the yoke and centering, reinstall the back and call it done.

It has very good sound for a portable with a single ~2" speaker. I'm also somewhat impressed how light it is for a 17" series string set. I like the engineering in this set. The chassis is held in by 2 screws at the top and slide tracks at the bottom with spring grabs to help hold it. It is also cool how the speaker is retained by a single spring clip at the back. They did a good job of protecting the CRT neck too...The entire neck is recessed a bit behind the chassis frame such that you would have to pierce the back dead center with something fairly small to have a shot at necking it. One thing I find weird is that a set with 3 IFs would extend the AGC out to the back and give it it's own user knob...I'd love to find a schematic to see if there is some electrical reason for it.

EdKozk2
05-21-2017, 08:39 PM
Nice job Tom,
If you post the model/ chassis number I could look up the Sam's folder for the set.
Ed

Marco-nix
05-22-2017, 11:08 AM
Hi Tom .. It's always nice to see these good old televisions come back to life. Too bad that there is nothing in French :( .. That's why I also have my forum in French.

Phil Nelson
05-22-2017, 04:14 PM
I believe the model number is 17D203 or 17D303 and the Sams is 447-3:

https://www.samswebsite.com/en/photofact/details/index/id/174132

Those Dualettes are cute sets. I keep waiting for an affordable one to pop up in this area.

Regards,

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

BigDavesTV
05-25-2017, 12:36 PM
Good job, Tom! I have been curious what it was like inside that Dualette, they sure loved the Bumblebee Caps! Looks like the CRT is strong as well, great score.

compucat
05-25-2017, 07:40 PM
Nice set. I hope the plastic isn't brittle. 1950s plastic seems to crack so easily.

Electronic M
05-28-2017, 12:33 AM
Thanks everyone!

Ed, it is a model 17D17R. A copy of the sam's would be great. I think the lin. pot may be open...I can get linearity almost perfect, then it jumps to a distorted mode and stays there the rest of the rotation.

Sorry Marco-nix, I don't speak a word of french. I know enough Japanese that I could probably do some half way convincing TV babble in that language, and I remember enough Spanish to ask how to get to the bathroom, but I don't know phoque about French. :D

The plastic seems fairly sturdy compared to some I've seen from the same time period.

I'm definitely going to treasure this set...I was planning to bid on a green dualette on ebay earlier this week, but it went for close to double what mine did and it was missing it's antenna and channel knob, not to mention the power 'knob' was off of it so it's connection fingers may have been damaged.

DavGoodlin
06-01-2017, 04:06 PM
Thanks for the great look inside Tom

I had NO idea how it would look :scratch2:but I'm not surprised and the PC board looks like a direct copy of the 17" metal set I have from a year earlier.