Remembrances of vacuum tube days

[mr__ed]

As a young teenager, I developed a love for electronics which became a lifelong love affair. In those days vacuum tubes were the norm and solid state devices such as transistors weren't in usage then. I built many projects using vacuum tubes as a hobbyist during my teen years, such as ham radio equipment, stereo amplifiers and tuners and various pieces of test equipment, all employing vacuum tubes. I obtained some of the early transistors' back then and tried to experiment with them, but quit trying to learn how they worked since I was so involved with tubes. Of course, my position changed in time. Many products we use today wouldn't be possible or feasible without the advent of solid state devices.

I also remember my first portable radio, which employed miniature vacuum tubes. I recall 2 batteries were necessary, a size D "A" battery, which supplied power to the tube filaments. and a much larger "B" battery, around 70 to 90 volts, which supplied power for the tube plates. The radio performed pretty well, AM & FM, as I recall. I also remember when most drug stores had do-it-yourself tube checkers available for the public. They're real dinosaurs now and nonexistent!

The older I get (now 76) the more I look back to the good ol' days of my youth! 🙂

[2oldman]

Gdetrailer wrote:
You are in the "stone age" my friend..Poke your head out the door once and a while..

I always look forward to your insults.

[wa8yxm]

georgelesley wrote:


Yes I remember the great tone of the old radios before “superhet’s” came along

I don't know that Superhet or Superregan made that much difference. though on a Superhet the passband was generally Tighter.

I am looking for a Knight Kit Star Roamer... Want one working, Likely will search E-bay for one.. This is a Superhet with a Regenerative stage..

The Radio is tubes (Save for the power rectifier) and the Regen was supposed to be used to "Fake" a BFO for CW reception (Or SSB but not that good at SSB) However if you adjusted the Regen (Front panel knob) just BELOW self-oscillation man did the RF gain go up... Stations you could barely detect were suddenly 5x9

It was also one of my first "Kits".. but alas that one is long gone.
I want one for multiple reasons

In other news.. Moving into an apartment is fun My Kenwood TS-2000 is now up and powered with a long wire for Receive only on HF and a Dual band Diamond V/Uhf on the VHF port. It's working at 15 watts on the VHF All I need for the ONE repeater I can hit from inside the apartment) I just found the long wire tuner. now I need to find the radio end of the cable to link 'em up Then I can "Tune" the long wire.

Ghost Wire will be used for an indoor long wire (Twin 16 ga wires buried in tape Stick it on the wall and hook it up)

Getting there. And I also plan on an MFG Mag loop Just for fun.

[Gdetrailer]

JKJavelin wrote:
I sure don't miss the electrical shock you can get from those tubes if you didn't ground them (yes, with the TV unplugged). I got it several times.
JK

Actually shocks were not just a "tube" problem it was very common in a lot of solid state equipment, that was caused by manufacturers being cheap skates and not using a transformer in the power supply and tying one side to the 120V line DIRECTLY to the chassis.. :E

It is called a "HOT" chassis and if not careful when servicing would end up biting you or worse yet becoming a pretty good arc welder when attaching serving equipment like oscilloscope ground to the chassis..

With most older equipment having non polarized line cords you can imagine the havoc that can cause when the HOT side of the line ended up on the chassis.

Spent a lot of my younger yrs servicing 1970s-1990s consumer stuff with one hand stuck in my pocket for safety.

And for the record, CRT TVs, the 2nd anode connection to the tube is to be respected.. CRTs can hold a second anode 20KV+ charge for YRS with out power, was taught to take a long flat blade screw driver and a clip lead from it to chassis ground before ever touching that connection..

[JKJavelin]

I sure don't miss the electrical shock you can get from those tubes if you didn't ground them (yes, with the TV unplugged). I got it several times.
JK

[Gdetrailer]

2oldman wrote:
The only product I'm aware of that still uses tubes is guitar amplifiers.

You are in the "stone age" my friend..

Poke your head out the door once and a while..

Found lots of brand new Tube audio power amps HERE

Been a revival rage for the last 5-10 yrs with a lot of small companies building them..



Pix of 35W per channel with USB/BT inputs..



Pix of 50W per channel with USB/BT inputs



Pix of Tube preamp..



Pix of tube headphone preamp kit

How about a McIntosh? Yep, they are still building tube stereo power amps..

[2oldman]

The only product I'm aware of that still uses tubes is guitar amplifiers.

[thestoloffs]

There are tubes, and then there are tubes!

Back in the "dark ages" (60's & 70's - my HS & college days), I used my 1st Class Radiotelephone license to work as an engineer for several 50KW clear channel AM stations in the Philadelphia area.

Their transmitters were so big in the pre-solid state days that we actually walked inside the room-sized cabinets and took off all our jewelry before entering (to prevent RF burns). We had to wear white linen gloves to touch any of the tube glass parts, because a broken tube could explode violently. (No OSHA in those days?!)

[Gdetrailer]

mr. ed wrote:

delwhjr wrote:
Started at a very young age by helping my grandfather and then my father repair electronics (TVs, radios and early HiFi rigs. I liked to build Dynaco stereos and loved my McIntosh stereo equipment. I still think the old tube type equipment has a better sound. I worked for many different electronics shops and went into teaching electronics after closing my own shop. I was always sought out by the local hobbyists to fix their Heathkits when they messed up. Eventually I got into computers and networking. When the students quit taking electronics classes(math was too hard :B), I changed to computers and networking classes. Retired from teaching at the Community college after teaching high school for many years.

Yes, I've heard the same thing about tube amplifiers having a "cleaner" sound. I doubt most people, except true audiophiles, could notice the difference compared to solid state. You mentioned Heathkits. I've built several in my youth along with many Knight kits. Included were ham radio receiver and xmitter, stereo amps and tuners, plus various test equipment (VTVM, oscilloscope, capacitor checker, tube checker, etc.)

Common misconception that tube amps are "cleaner", in reality they are not. What you do get is a slightly DIFFERENT sound sonically, some would say a "warmer" or "fuller" sound that what transistors give. Hard to describe..

Some folks say transistor outputs as being "sterile" compared to tube outputs.

Back to the "cleaner sound" for a second, tubes by nature inject considerable amount of noise into the audio signal. This happens as the filament heater gives off electrons, some of those electrons affect/interact the plates and grids electrons in the process.

Additionally, most tube amps the filament heaters are powered with a AC voltage which if you listen with a good set of headphones you will be able to hear a slight AC 60hz hum in the background with no signal. With good headphones you can also literally hear the electrons hitting the grids and plates in a form of white noise in the background with no signal. Add that background noise to your music and it gives the 1950's "HiFi" sound that you and your parents grew up with.

There are simulators you can add to your system that can add in a simulation of a tube amp if you like.. They also make tube preamps if you like..

[BobsYourUncle]

Being an air force brat, I lived at CFB Cold Lake Alberta in the late 60s.

In 69, at age 15 I volunteered for a DJ position there. I had my own Friday and Saturday evening shows for playing teen music. My theme song was "Friday On My Mind" 1450 CHCL "Chuckle" Radio!

The whole radio station was all old tube equipment, and would go down once in a while. I remember looking into the amps and broadcast equipment at all those cool looking tube things, and learning that if it isn't glowing, it has likely failed.

There were 2 control rooms, each equipped with turntables, control boards with pots to adjust sound and inputs etc.

Sometimes one control room would go down, and I figured out on my own how to use big patch cables they had to run the output of one room into another. I would get it up and running while the service tech would come fix the problem, usually a blown tube. It only happened a couple or few times, but I was totally fascinated at all that neat-o electronic equipment.

Even as a boy I loved to play with little electric motors such as those battery operated Meccano set ones, little flashlight bulbs and batteries, wires I could fiddle with to do things etc.

In about grade 6 I won first prize for the best Halloween costume, a robot. Wearing cardboard boxes covered in tinfoil from head to toe, I ran wires, flashlight bulbs, a motor with propeller on the top of my head and more. I ran all the wires and taped the bared ends to my fingertips. The thumb was power and the other fingertip wires fed the various lights and such. I walked around touching my fingers to my thumb for the blinking, propeller spinning robot effect.
Yeah, great memory for an 11 year old!

That DJ experience was the beginning of getting serious about the hobby. I took electricity and electronics in high school, graduated with the intention of furthering my education and finding work in that field, but wound up taking work in home renovation instead for a while. 45 years later, I'm still in that industry.

[mr__ed]

delwhjr wrote:
Started at a very young age by helping my grandfather and then my father repair electronics (TVs, radios and early HiFi rigs. I liked to build Dynaco stereos and loved my McIntosh stereo equipment. I still think the old tube type equipment has a better sound. I worked for many different electronics shops and went into teaching electronics after closing my own shop. I was always sought out by the local hobbyists to fix their Heathkits when they messed up. Eventually I got into computers and networking. When the students quit taking electronics classes(math was too hard :B), I changed to computers and networking classes. Retired from teaching at the Community college after teaching high school for many years.

Yes, I've heard the same thing about tube amplifiers having a "cleaner" sound. I doubt most people, except true audiophiles, could notice the difference compared to solid state. You mentioned Heathkits. I've built several in my youth along with many Knight kits. Included were ham radio receiver and xmitter, stereo amps and tuners, plus various test equipment (VTVM, oscilloscope, capacitor checker, tube checker, etc.)

[vermilye]

I remember an interesting part of the shift from tubes to transistors. The radio controlled model airplane receivers were vacuum tube models when I started. Miniature tubes, but still the receivers were pretty big.

The president of our model airplane club owned a hearing aid company. He arrived at one meeting with a hand launched glider that he flew around the meeting room that had rudder control. He had his engineers build a transistorized 27Mhz receiver that was about the same size as the rubber band actuator. Impressed the hell out of all of us.

[georgelesley]

wa8yxm wrote:
You can still buy Tube amplifers and receivers if you know where to look.

They have a "Sound" that is quite a bit different from modern "Solid State" stuff. Much (And yes I know this sounds somewhat like a pun) "Warmer".

(The pun is that due to the filament heaters and other sources a big tube amp can heat your room)

Yes I remember the great tone of the old radios before “superhet’s” came along

As an avid “DXer” on the AM band (before FM was common), I thought I had died and gone to heaven when I found a radio with a three gang variable tuning capacitor or condenser can’t recall which we called it..

[georgelesley]

I have to tell a true story of the late 1950’s. We had just gotten our first black and white TV, it died. My bedroom was just a bed in the unfinished basement. The TV was moved there. I was a teenager at the time and had a bicycle propelled paper route and there was a radio/TV repair shop on the route. The shop owner never had to pay me for the paper, I was always buying parts for something from him. Anyway, I told him what it was doing, I think it was a vertical or horizontal stabilizer control issue (remember those).

He told me to bring the tubes to him and he would test them. Sure enough one was bad. A new tube and the TV worked again. For almost a year I had a working TV in my bedroom and nobody knew it but me. I could only use it after everyone else had gone to bed upstairs and had to keep the volume down, but mine alone. Mom also stored her home baked cookies in the freezer next to my bed. I rotated which bag I raided to make it less obvious what I was doing, but I think she was wise to me.

One night after we all went to bed, dad surprised me eating cookies and watching TV, with an unexpected visit. The next day the TV was back up stairs.

Anybody remember Heath kits and Lafayette radio?

[roam1]

Those were the days, when you had to figure something out or order the Sams schematic. My journey started in the 60’s when a friend of my grandfather invited us out on his yacht on Lake Michigan, At the end of the ride I was presented with a electronics study kit by our host, Mr DeVry. I loved to take things apart and see how they ticked. Then there was 2 years of high school electronics which I convinced the teacher to open a 3rd and 4th year so I could do self study. At the age of 16 I walked i to the local electronics repair shop and inquired about a job. The owner sort of chuckled but then sat down with me and drew some circuits out for a test, 30 minutes later I was on the bench repairing equipment and making $5/hr which was 3 times the minimum wage! Tubes were my favorite cause with very little documentation I could fix most gear. Then came an EE degree and a job at a small semiconductor company in Silicone Valley that Andy, Bob, & Gordon started, but that’s another story.

I still have a H H Scott 299B stereo tube amp and a Decware “Rachael” in my shop keeping me warm 🙂 along with tube testers, VTVM, variac.....

I don’t know if I would have gone that path if I had not met Mr DeVry so my favorite gifts to nieces and nephews is something that they can learn from and grow.

[wa8yxm]

You can still buy Tube amplifers and receivers if you know where to look.

They have a "Sound" that is quite a bit different from modern "Solid State" stuff. Much (And yes I know this sounds somewhat like a pun) "Warmer".

(The pun is that due to the filament heaters and other sources a big tube amp can heat your room)