Newcomb B-100 Schematics

Seems there are 2 different versions of the Newcomb B100 radio. An early one with octal tubes and a later one with 7 pin mini's. Top radios is the newer version and the bottom is the older. Right click on each picture and select "open link in new tab" for the full size version.

This is an under chassis picture of the early model

 

This is an under chassis of the newer model.

Here is the schematic for the new model.

Here is the schematic for the older model.

The older model is better in my opinion. Sounds better and works better.

Sears Silvertone 5009

Here is an AM radio I picked up from ebay.

It was listed as "for parts not working". The original picture showed it was very dirty. When I got it it had a bunch of problems. It took about 2 days to track them all down. I thought it had silver migration disease in the IF filters (it did not) I recapped it, I had to go through the circuit board and re-solder EVERY component. I had to tighten up and solder the tube sockets, In the process of working on it I broke a very fine wire on the oscillator coil and had to fix that. I replaced a few resistors. I took it apart and cleaned the case with simple green. I did a full alignment, and the only thing left is to fix the melted plastic on top and replace the interlock cord.

Motorola B12WA

When I was a kid we had one of these.

It died in the late 70's. I took it apart and trashed it. I found one on ebay.

Goodwill Haul

Being recently revenueless I kept busy fixing old radios and going to thrift stores and estate sales. This is a partial list of my haul for the last 12 months 7-2012 to 7-2013:

Magnavox 20mf500t/17 20" LCD TV
Shure 520DX
Eico VTVM
Line 6 Spider III amp
2 geiger counters
2 minimus 7's
2 veneered minimus 7's
WinTV-hvr 1600
Pioneer SX-3600
orphaned Mini Advent
wireless shipping scale
Technics SA-5460
supro S6606
Center Channel Design Acoustics PS-CV
Sansui 200
Optonica SA-5407
Proton 740 tape deck
Hewlett Packard 120b tube oscilloscope
Yamaha Natural sound GE-30 Equalizer
1 Optimus unknown speaker
1 Denon TU-450
2 Garrard GSS100 speakers
1 realistic mini amp
realistic mini tuner
Technics SA-GX130
Technics RS-T330R Tape deck
optimus pro-x88av
Garmin Etrex Legend
AC hookup wire
Technics SH-8055 12 channel GEQ
Technics SU-V57 integrated amp
Technics ST-S77 tuner
Technics RS-B17W tape deck
several Canon T-50 cameras
Many SLR Cameras and lenses
Yaesu FT-23R
Kenwood KT-42B
Fender Frontman 15G
Marantz SD155 Tape Deck
Optimus SA-155 "amp"
NAD Monitor Series Power Amplifier 2100 Power Envelope
Luxman Tuner Preamp TP-117 with BOTH remotes
Fisher DS-810 speakers
General Signal PC-150 line conditioner/isolation transformer
Ross Electronics Co. 2101, 8 band radio
craftsman 1/4" socket set
Technics SA-301
Yamaha A-32
Audiosource AMP One/A
Triad Bronze Powersub
Pioneer PL-115d
Kenwood KA-127
Fisher 215
Coral BX-200 speakers
Sansui 7070
Digital I.C. Color Generator
Polaris MT5500 marine radio
Sporty's E6B Flight computer
Technics ST-G5
GE el cheapo tube radio

Most Items were sold.

Lloyd's TM-75 Tube Radio Schematic

Lloyd's TM-75 Tube Radio Schematic.

 Uploaded these for anyone else who has one and needs the schematic and tube layout.

Click on each image for a larger version.

Refurbishing a General Electric C403D Tube Radio Part III

Radio is done for now. Just a few things left to do. Which may take a while.

Refurbishing a General Electric C403D Tube Radio Part II

Work is progressing on the little radio. I have the grill on the bottom. 

The speaker and speaker cloth are installed.

I located a speaker grill at Ace hardware. It is a brass plated shower drain guard. It was a huge pain to mount. there were 4 small tabs on the back to hammer down, I had to solder brass screws to the back of the "grill" which involved scratching up the surface, using acid flux and plumbing solder since rosin core would not do it. I had to modify the speaker to match the screw locations. There is the possibility that it could pop off at anytime since I do not have much faith in it being properly soldered (we will see). although it is not magnetic it seems to not be solid brass. When I scratched up the back I uncovered a nickel? colored metal.

I have attached a home made and artificially aged (with coffee) label on the back plate.

SO! what's left to do?

The transformer.
Better knob and dial.
Dial markings (dependent on dial).
Finish the back

all the above may go slow but the transformer and back will probably be done late this week or early next. Knobs would probably take sometime.

Refurbishing a General Electric C403D Tube Radio Part I

So a while back I purchased from ebay a radio similar to this:

 for parts not working.

Well I got it working but the clock would not keep time, the plastic case was ugly, and I do not like clock radios anyways.

I pulled the guts and gave it a newer better speaker.

 I decided to put it in a new cabinet. However it is 108 here and I had no interest in trying to build a cabinet in the heat. I went to Micheal's and picked up a small non square box to put it in for $5.00.

I then removed the lid and hinges, and glued in some supports for the components and for the back.

I drilled holes in it for the tuning knob and volume.

 

 I temporarily mounted the board in the radio sideways like it was in the original. I will be drilling 1 or more holes in the bottom of the cabinet later to get some air flowing over the tubes.

 I made a cutout of the speaker so that I could place it correctly. The tuning dial and volume knob are from the old radio and will probably not be going on the new cabinet. I found that I needed to move the speaker over about 3/8" from my initial placement. The speaker hole will be cut out and some cloth I picked up will go over the speaker, then I will make a decorative flange to go over the speaker and cover up the speaker hole.

 I had purchased some large beads for the feet and attached them.

I went looking for a prefabbed cutout for the speaker and could not find anything, both at craft stores and on line. I will have to keep looking as I do not have the proper tools to make what I want. I did cut out a hole in the bottom and found a small chrome fan grill to keep probing fingers out.

I also gave the wood I nice stain. However that uncovered a flaw on the bottom of the craft box. It has scratches at right angle to the grain. I had sanded the face (with the grain) but did not see it till it was stained. Oh well it gives it character. 

I have the following completed. I have figured out where to wire the pilot light. Installed the mp3 input on the board, and put on a thin coat of spray varnish. Now she needs to dry overnight. When I put the feet on this time it sits perfectly without rocking. 

Fixing a Consus Eagle USB drive

I have had a couple of these Eagle/Consus External hard drives for a while now and over the years they have given me fits. After a few months of use they start to have problems.

Usually the problem is caused by the the cheap AC adapters failing due to bad capacitors. Today I checked on my servers backups and found they have not been backing up in weeks. NICE! I cracked open the AC adapter and checked the caps and they are all fine... hmmm. I took the drive apart and everything looked ok, but I pulled one of the caps and tested it with my Atlas ESR+ and it showed out of tolerance and rather high internal resistance of 8ohms. So I pulled all the 100uf 16v caps and replaced them. They were all out of spec and had internal resistances as high as 17ohms.

Before finalizing the work I tested the drive and found that everything was working like it should.

So I finalized the repair and will do the same with the other drive I have.

Why would I bother fixing something as inexpensive as a USB enclosure? Because I hate to throw out something perfectly good if I can fix it, and I am cheap.

Newcomb B-100 Radio Restoration

I recently got 2 Newcomb B-100 Radios off of ebay. Newcomb made radios from the 40's to the 70's (I think) I cannot find much info on the company. Their radios, and other equipment were used mostly in schools. These 2 radios are slightly unusual because they are more "fancy" looking than their other models.

 The bottom one in is the older radio and the subject of this post. It was very dusty inside and surprisingly (for it's time) has a transformer.

 First thing I had to do was replace all the red beauty capacitors,

 With orange drops and 2 of the cpacitors with some Red Audiophile Capacitors. I also installed new electrolytic capacitors (not shown) but left the old multisection cap installed for looks.

  I replaced a few out of spec resistors, the power cord, moved the fuse to the back of the unit, and replaced some of the wire that connect to the antenna and speakers. I installed a 3.5mm audio in jack for playing MP3z through the radio. This radio already had a Phono circuit so it was easy to do.

 I made new labels to go over the old identification marks stained them with coffee, and covered the hole where I removed the audio out jack.

I need to recover the case and that will be fun as I do not yet have a source for the vinyl cloth to do it.

If anyone has any of the schematics or other documentation for these radios please contact.

Idiocracy

You know what do.

Hallicrafter S-38 (Original)

My sister (while Antiquing) Spotted an old radio for about $40. I asked her to describe it and it was a Hallicrafter S-38. I almost did not have her buy it, but after looking on ebay at similar ones in similar condition, it was not a bad deal for a non working tube radio. So I had her get it.

This one was made on June 3, 1947, and it was in pretty crunchy condition as seen here:

 It needed a lot of work. I ended up replacing all the electrolytics ( the big Yellow can with wires out the end), All the paper caps (the brown waxy looking cylinders), all the Resistors, Some of the crunchier wiring, the speaker, and 4 of the mica caps. I also replaced 1 tube, someone had put a 50L6GTin place of the 35L6GT This is the after pic.

 Theses radios are a bit on the dangerous side and the chassis is hot (electrified). The chassis is insulated from the metal case with 4 rubber grommets. I picked up replacements at Ace Hardware. I also replaced the missing power cord with a polarized one and made sure the hot wire goes to the switch. Everything went well until the antenna ground touched the case (black scorch mark on the chassis between the brown ovals in the pic below). So now the CW circuit does not work right. Everything else works fine.

 The CW circuit is used to listen to old style radios with Morse code and it is helpful in tuning in a station. It is not really needed but I am bummed it is not working. I am researching a fix.

Otherwise it is a great little radio.

Refurbishing a Trailer Part VII

SO here is the Trailer with lights and wiring installed. We finished painting it this morning.

 We installed the chains.

 Here is the completed trailer.

 We decided not to install the fenders at this time.

 We got 2 sheets of plywood and Chris painted them with some redwood stain no.9.

 Registration will come later.

It almost looks like professionals did it.

This is your Government

If the Media were part of the solution...

Refurbishing a Trailer Part VI

 So we are on the home stretch. This weekend we prepped the entire underside of the trailer for painting. We found some paint that is supposed to turn rust in to a protective coating.

 We painted all the leaf spring parts and the leaf springs. Re-assembled everything. Drilled holes in the bolts for the cotter pins. Then painted everything on the underside of the trailer.

 At this point the remainder of the work needs to be done in the front yard as we would not be able to easily get the trailer through the gate with the wheels on.

 Once the axle was attached to the leaf springs we flipped the trailer over.

 

We installed the brake lights and wiring and took it on a very short test drive. I forgot to take pictures of the brake lights and wiring and will post that next week.

What is left to do:
Install the fenders.
Paint the top side of the trailer.
Install wood floor and side boards.

Register the trailer.