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Hi,

Perhaps you may like to follow along with this high dollar ($10.00) transistor amp build...lol I was going to do a video but decided not to. To lazy to dress up and shave...lol

Here is the start of this mess.

I have never built a transistor amp and I am finding everything way to small and fidgety!!

Billy
Originally Posted By: Planobilly
Hi,

Perhaps you may like to follow along with this high dollar ($10.00) transistor amp build...lol I was going to do a video but decided not to. To lazy to dress up and shave...lol

Here is the start of this mess.

I have never built a transistor amp and I am finding everything way to small and fidgety!!

Billy


Following. I've also built myself a 10-buck amp, though it was slightly over 10 bucks since I put it into a 1590A enclosure that was 8 bucks on it's own. Of course, I'm talking Canuck bucks, so ymmv.
Hey Simon...I tried to build this on some eyelet board. The type you would find in 1950's Fender amps. It is too thick to get the pins on the op-amp socket through. I could point to point wire this but that looks like crap.

I ordered this, have no real idea if it is the right type board material or not. Solid state is a new world for me.

PCB Board: 30 pieces double sided PCB prototype boards in 4 sizes, Double sided board with plated-thru holes allows components to be easily soldered to either side of the board
3 Types of Header Connector: 10 pieces 40 pin male header, 10 pieces 40 pin pitch right angle male headers, 10 pieces 40 pin female header; pitch: 0.1'/2.54mm, single row and straight connector
2 Types of Terminal Blocks: 5 pieces 2.54-308-2P and 5 pieces 2.54-308-3P; Pitch: 0.1'/2.54mm
Jumper caps: 30 pieces standard 2.54mm pin spacing circuit board jumper cap
100 % SATISFACTION GUARANTED: General purpose prototyping circuit board for analog and digital use; With pre-tinned plated holes; Extra accessories to make life easy for you (Screw Terminal Block and Headers)

It only cost a few dollars and I hope it works because I want to build some other Transistor/IC device for a CNC machine I am building.

Amazon would save money if they just parked a truck at my house...lol

Billy

EDIT: We are actually going to play live tomorrow after noon at a small private party. Everyone has had their rabies shots...lol
Messing around with a eyelet board. Amazon will deliver the prototyping boards tomorrow.

Not likely to burn out the 650 volt cap...lol

Trying to build this sort of stuff on a eyelet board and soldering the wire to the socket for the OP-Amp is not very easy to do. Stuff like this needs to be built on a PCB.

It would be OK on a turret board if I had small enough parts to set the socket in.

Onward through the frog...lol

Billy

Still messing with eyelet board. Hope new prototyping material gets here today. Eyelet board is not a good solution for such small components. Perhaps there exist smaller eyelets??



Billy
The prototyping material arrived and looks like it has some advantages.

For the moment I am at this stage with the eyelet board.



Billy
Well, have you cranked it up? I feel slightly responsible to make sure you get this going grin
Originally Posted By: VideoTrack
Well, have you cranked it up? I feel slightly responsible to make sure you get this going grin


Thanks, be advised I will be bugging you if I can not figure it out!!...lol

I have been slightly distracted by a live gig. Happy stuff!! Also studying Spanish. New pretty spanish girl moved in next door. Wife will kill me but I can't say exactly when....lol

I have not done any electronics for quite some time so I am really slow. Can not remember the resistor codes, cap codes, is the long leg positive?? So many questions, so little time...lol

Perhaps today or tomorrow we will check for smoke!

Billy
Well, close but no cigar. I put a small signal from a battery CD player into the input and ran the output into a large speaker system. Pilot light works, the signal gets amplified but nothing but popping noise from the speaker which gets louder with increased gain.

The boss is demanding I return to my fulltime job on the honey do list. So, trouble shooting will have to be delayed till later today when she takes a nap...lol Only good news is no smoke!

Off the air for a bit.

Billy
Billy and all.
a question for the guitar amp gurus.
one of my favorite all time rock songs is hold on loosely by 38 special.
WHAT GUITARS AND AMPS DID THEY USE ON THIS GREAT SONG ?
some say peavey amps ? i just got this odd feeling hi watt perhaps ?
but maybe thats a daft idea.

i'd like a buck for every time ive jammed along with it.
always love the way the F#minor was used etc etc.
the lead guitarist, totally brilliant talent imho. wonderfull licks etc.
i always think i'm not worthy playing along lol.
well i'm no great guitarist anyways imho.
just can play along rhythm/do some of the lead licks.

anyone know where it was recorded ?
by comparison the stuff today on the song charts just dont crank me up like loosely.

btw billy/all. you seen the new tiny fender amp mustang you plug into the guitar jack ?

best
1-love-to-rock-out-old-muso

I saw them live a few times and recall one played what looked like a Les Paul Junior. That was the singer who also played some guitar. One of the lead guys played an Explorer. And the other lead players played like an old Melody Maker looking guitar. I was never close enough to see nuances but those were the body shapes. If I recall the lead guitar guys were named DOn Barnes and Jeff Carlisi with Donny Van Zandt being the lead vocalist who added rhythm guitar when there were dual leads.

They were a "funny" band in that they made the rep as a southern rock band but "Hold On Loosely" wasn't all that southern rock in the vein of what the Allman Brothers and Marshall Tucker brought to mind. And to a lesser degree Wet Willie. Wet Willie lost me when they started fighting about the name when the Hall family split in half. I preferred the half that Donna went with because she was hot...
Eddie.
re loosely.
thanks for the info. any idea of the amps they used ?

fyi. a band that surprised me live. and my vote for #1 live band i ever saw was Steppenwolf.
ive seen lots of top bands over the years live. and had various disappointments includeing screwed up (oh lets just get through this) lead breaks.
BUT NOT THEM. every song was on the money.

what impressed me was even though they had played the songs obviously many times before; they were really enjoying themselves with gusto, and enjoying the audience feedback, which was huge. in summary i was totally impressed by their attitude.
fantastic sound also. when i saw them last they had this very talented young lead guitarist. useing marshalls if i remember.
wow did he get a great guitar sound.

cheap trick also really impressed me live.
look at the song inventiveness of CT with b carlos on drums. i just dont hear these type of great songs today and riffs. or maybe i'm getting old. lol.

best
oldmuso
ps with my new audient evo interface is a free download
of a guitar plug in from 2 notes engineering.
gonna try it soon.
https://audient.com/arc/two-notes/
Billy, you learned how to type on one of these, right?

Originally Posted By: justanoldmuso

thanks for the info. any idea of the amps they used ?


I was never close enough to tell.

I remember asking one of our guitar players why he continued to slow down our show by changing guitar EVERY song, and of course then also having to tune it. That broke the flow of the set. He gave me the standard answer of every guitar pla7er who wants to show off how much money he has, which is always "Different songs call for different sounds." At that point I looked at the 127 pedals he was running through and said "You plug in there. The sound comes out WAY over here. By the time it reaches the amplifier it all sounds exactly the same no matter what guitar you are using. 7 distortions, 3 phase shifters, 5 flangers... can you just once sound like a GUITAR??"

He didn't talk to me much after that.

AND, one of them was a Variax. Why have a modeling guitar if you are not going to "model" with it?
Actually Eddie I only had a goose feather quill to write with...lol

ON a more serious note.

First transistor amp build try not working. How the Ruby Works ( schematic at Rob Robinette.com)

I know next to nothing about solid state. Trying to trouble shoot.

I injected a 1000Hz signal at 250mv. Have correct wave form at gate. Have 9 volts at drain. No signal at source of of j201 JFET. 4K resister to ground from source verified. Schematic calls for 3.9K but I did not have one. I assume 4K will work. There may be other issues but I assume I have to solve the JFET buffer issue first.

The amp produces noise and popping/motor boating and noise is increased with increase of gain and volume control so I assume the LM386 is at least producing some amplification.

I ASSUME JFET is bad. Am I correct n this assumption?

Thanks,

Billy

Sorry to have to ask such basic questions...this solid state is a new world for me.
You should have the same waveform as your input at the Source on the JFET. The device is only acting as a buffer.

The JFET might be in backwards?

Try taking the JFET completely out of the circuit and connecting your signal generator to the 47nF coupling capacitor (the original Source terminal) That will prove if the JFET is faulty (or in backwards).
There's a data sheet for the FET at this site:

N-CHANNEL JFET. J201 Datasheet
The JFET issue has become a PITB! I decided to build another amp on a push pin board so I can test things and pull them apart. I have a transistor tester but but it is not designed for JFETs. I ordered a new more modern tester that can read a JFET.

Some stuff from Amazon and ebay is hard to deal with...no data sheet.

I have Fairchild JFETs coming in a day or two. Meanwhile trying to figure out the pinout on the JFETs from Amazon.

Learning many new things about solid state. Video Track has helped me a lot Thanks man!



Billy
Wow, that brings up my memories of electronics school in the 80s. I went to DeVry.
I am trying to envision what it would be like to have a bunch of firemen as friends, because if I ever tried to build something like this, they'd be at my house a LOT!
Originally Posted By: sslechta
Wow, that brings up my memories of electronics school in the 80s. I went to DeVry.


Hi Steve,

I just one day decided I wanted to learn how to repair tube amps, mainly because we had one in our band that was always giving us trouble. I started building amps and things got out of hand pretty quickly...lol It was and still is a challenge. This little dive into solid state has been a pretty steep learning process also.

At my age, I am not sure I could deal with formal school though I am sure it would be very helpful. I have been considering getting a professional to start teaching me Spanish at a much deeper level. It was never my plan to be here in Miami long term. I have become friends with people I really like and need to get past basic Spanish. Taking a formal class two days a week past seventy was also not something I planned for...lol

You should have not let it be known you went to electronics school. I will be bugging you with questions...lol

Billy
Originally Posted By: eddie1261
I am trying to envision what it would be like to have a bunch of firemen as friends, because if I ever tried to build something like this, they'd be at my house a LOT!


Fire is the least of it Eddie...lol Here is some stuff that would scare most people to death who understand it!!...lol

690 volts AC for testing.


110 volts for testing.


No one but me works on stuff here so it is sort of like having a loaded gun setting on the coffee table. I know to keep my hand off the trigger...lol
The hi voltage stuff can easily kill you. Even when a tube amp is unplugged there can be charged capacitors that can kill you.

Not as dangerous as flying choppers in Vietnam but pretty close...lol But then I often go cross the gulf stream to the Bahamas in my boat by my self...been crazy for a long time...lol

This boat is huge when I have to clean it up. It gets pretty small about 50 miles offshore...lol


Billy
What do you pull that with? A tank? That small truck seems like it would strain under that weight. Unless it has a bigger power plant than what it looks. Mt friend Andy's boat comes in at 3750 but he has a really heavy duty trailer. One time he was n a jackpot because he had not yet bought his truck and the one he had access to had a blown head gasket, and he had to move the boat to a shop. I offered to do it with my car until I heard the weight, because my max towing weight for my car is 1500. My little trailer only weighs 700 and it tows like it isn't there.

I might pick up a 12 ft aluminum boat with a trolling motor next year. Where I live there are a ton of small inland lakes. I have about 5 just within a 20 minute drive. I have dropped a line into every one of them at some point, but I fish like "Catch fish... don't catch fish... Whatever. I'm just here for the silence and solitude."

Here's a quick map of my fishing spots. And remember, I live in the city. And this is just what is south of me.


Hi Eddie,

The boat is over 10 thousand pounds, actually around 12 thousand I think. The truck is a Nissan Titan with 315 HP and a good amount of torque. The boat stays in the water at our dock behind the house in Marathon Florida most of the time so it is not an everyday event to get the boat out of the water. We have a new Chevy 2500 HD also that pulls the boat a little better than the Nissan. I have installed 5000 pound air bags on the rear axal of both trucks. Both trucks are used to to pull a 30 foot cattle trailer loaded up with claves. Towing has never been a real issue.

I don't know what the future will be. I am getting to old and weak to haul the big fish over the rail. We also have a zillion lakes and rivers here. A small boat sounds like a good plan for me also.

My plan was to be living in southern France by now. It is just not going to happen for many reasons.

Getting old sucks...lol To many "I can't do this any longer" No more flying airplanes, no more working a hundred hours a week, perhaps no more running around in the ocean very soon, and no more four set gigs. Plus I had to stop chasing cars and howling at the moon!!...lol

I can't really complain...like Joe Walsh said "life's been good so far"

Not sure how we got so far off the amp thread but I am taking it easy today, no pressure.

Billy

Billy
Billy, Solid State is Great.

(And you can't blame me if you zap yourself on the 9 volt battery grin )
You guys who can build amps I assume had formal electronics training to know circuits like you do. What kind of training goes into that? Do you have formal degrees in electronics?

I have a long time friend who was offered a 4 year ride to MIT on some kind of Eastman Kodak scholarship program. He DECLINED and went to work delivering appliances for a local business. And he worked that job for 25 years until the business closed. His logic? "I just finished 4 years of school. I don't want to go to school anymore. And for what? So I can sit at a bench and solder circuit boards all day?" And then headed into adult life with constant financial problems. Had he gotten that degree from MIT the world would have been his oyster, and with his creative side he would likely have been designing those boards, not producing someone else's designs.

When the world hands you a gift, accept it with grace and move on.
LOL...well I am sure I could charge up a cap with a 9 volt battery that would wake you right up.

Solid state is great. It opens up a whole new universe of possibilities.

You need to come to Miami and visit me. Plenty fun stuff to do here that I can take you around to do and see.

Of course there is about 10 boxes of old carbon resisters I could use a hand sorting out...lol This is what purist demand when repairing vintage amps.

I am sure I must have over 5000 sorted resistors of several types on hand, funny, I am not sure how it could be possible not to have a 3.9K I needed for this little amp...lol



Billy
EDIT: I got these by the pound from an old radio/TV repair shop. They are a bit of a pain to use. They require testing each one (really need testing under a load) and sanding down the leads to remove the years of oxides. I got around 10 pounds as I remember.
Here, I'll help. This one with the arrow is a 6.8M Ohm with a tolerance of 5%. Actually, they all look like carbon film, pretty old technology, I think.

(well, just tryin' to help grin )



Attached picture 2021-04-28_23-40-04.jpg
Originally Posted By: Planobilly
Here is some stuff that would scare most people to death who understand it!!...lol

690 volts AC for testing. PIC1


110 volts for testing. PIC2


No one but me works on stuff here so it is sort of like having a loaded gun setting on the coffee table. I know to keep my hand off the trigger...lol

Yeah, that first pic scares me a little. There's some juice there.

For the second photo, I have several of those plugs lying around for testing wiring. I ran my own underground wiring from my back yard patio to the house, about 30 feet. I used plugs like that during each phase to make sure I wasn't trashing the wiring as I went.

Originally Posted By: Planobilly
You should have not let it be known you went to electronics school. I will be bugging you with questions...lol

The 80s also happens to be the last I was heavily involved in electronics. I ended up switching majors and although my degree is AAS in Electronics Technology, I had switched over to mostly computer science topics. So I'm kind of a jack of all trades in technology.
Originally Posted By: eddie1261
You guys who can build amps I assume had formal electronics training to know circuits like you do. What kind of training goes into that? Do you have formal degrees in electronics?

I have a long time friend who was offered a 4 year ride to MIT on some kind of Eastman Kodak scholarship program. He DECLINED and went to work delivering appliances for a local business. And he worked that job for 25 years until the business closed. His logic? "I just finished 4 years of school. I don't want to go to school anymore. And for what? So I can sit at a bench and solder circuit boards all day?" And then headed into adult life with constant financial problems. Had he gotten that degree from MIT the world would have been his oyster, and with his creative side he would likely have been designing those boards, not producing someone else's designs.

When the world hands you a gift, accept it with grace and move on.


Eddie, lots of people have degrees in electronics and many could build most anything they would like too. On the other hand if they went to school in the last twenty years they most likely have little idea how a vacuum tube works. Others have learned on their own.
Some like me just jump in with both feet knowing nothing and are lucky enough not to kill themselves.

One of the most famous amp builders had no formal education in electronics. Leo Fender studied accounting at Fullerton Collège. Here is a link worth reading.
https://en.wikipedia.org/wiki/Leo_Fender

While you will not find my name listed in wikipedia the people who are will likely be just as unknown to you and others. Bruce Zinky, use to work for Fender as a amp designer. Mark Sampson who started Matchless amp company. Alexander Dumble designed what many consider the world's greatest guitar amplifier – if you want one, it'll cost you $50,000.
These people are certainly not household names. I could go on listing names only because I have an serious interest in guitar amp, guitar, and music in general.

This little solid state amp I am building I would have had up and running in a couple of days if my only interest was to build a working amp. I am trying to learn some solid state electronics and digging into subjects as arcane as understand what Bypass decoupling path on pin 7 of the op-amp actually means and how the value of a 100nf capacitor was derived.

The fact of the matter is it is not necessary to know much of anything about electronics to build a tube amp or transistor amp . All you need is to be able to read and follow instructions.

There are a few skills like learning to solder you have to acquire. DIY kits are readily available on the internet for sale at various levels of complexity. A million tutorials exist on youtube.

Learning electronics is not super easy but a lot less work than becoming a really good piano player.

Go to MIT if given the opportunity but don't let the lack of formal education stop you from doing anything you set your mind to do.

Learning new stuff can always be a challenge. Many kind people here on this forum have helped me to learn BIAB. One or two have advised me in no uncertain terms to go read the damn manual...lol You sometimes have to wade through some mud before you get to cross the river...lol

Enough soap box....back to work!

Billy
Originally Posted By: VideoTrack
Here, I'll help. This one with the arrow is a 6.8M Ohm with a tolerance of 5%. Actually, they all look like carbon film, pretty old technology, I think.

(well, just tryin' to help grin )



You got good eyes. The 5% gold band does not look exactly like gold in the photo but what else would it be. The grey was not that easy to see also.

They are old...most likely from the 1960's.

Billy
Originally Posted By: Planobilly
The hi voltage stuff can easily kill you. Even when a tube amp is unplugged there can be charged capacitors that can kill you.

Not as dangerous as flying choppers in Vietnam but pretty close...lol But then I often go cross the gulf stream to the Bahamas in my boat by my self...been crazy for a long time...lol

This boat is huge when I have to clean it up. It gets pretty small about 50 miles offshore...lol


Billy




Nice boat. Contender?


Regards,

Bob
Hi Bob,

Yes, a 28 foot Contender. My dock is only 32 foot long so to get a bigger boat I need to sell the house and buy another one. My pardner and I have talked about that a lot but taken no action.

I don't need another boat, truefully I don't need this one any longer. The last two times I have gone fishing I have chartered a boat. My business partner is to busy working to use the one we own. We are both old enough that a open center console boat beats us up pretty bad.

Contender is a pretty good fishing boat and for sure very seaworthy. I have been in some real XXXX weather on occasion without issue. The boat has always been a little small for the type of use I put it to. Only 180 gallons of fuel being it's is the main problem.

[img]https://i.imgur.com/jADrPGp.mp4[/img]

Perhaps if I would loose about 40 pounds boat life would be a bit less of a problem...lol



Forty miles off Marathon in 1600 feet of water, a small swordfish. Man, just talking about all this makes me want to go fishing!!

Billy

My 1st trip down was in 1954. The old Southernmost motel in Key West. I was only three, and have loved the Keys ever since.

Can't stand to see it now. I prefer my memories.


Regards,

Bob
Originally Posted By: Planobilly
Hi Bob,

Yes, a 28 foot Contender. My dock is only 32 foot long so to get a bigger boat I need to sell the house and buy another one. My pardner and I have talked about that a lot but taken no action.

I don't need another boat, truefully I don't need this one any longer. The last two times I have gone fishing I have chartered a boat. My business partner is to busy working to use the one we own. We are both old enough that a open center console boat beats us up pretty bad.

Contender is a pretty good fishing boat and for sure very seaworthy. I have been in some real XXXX weather on occasion without issue. The boat has always been a little small for the type of use I put it to. Only 180 gallons of fuel being it's is the main problem.

[img]https://i.imgur.com/jADrPGp.mp4[/img]

Perhaps if I would loose about 40 pounds boat life would be a bit less of a problem...lol



Forty miles off Marathon in 1600 feet of water, a small swordfish. Man, just talking about all this makes me want to go fishing!!

Billy



Don't think I would want a wrestling match with that fella! you are welcome to him...lol
It is not really much of a wrestling match. This is day time swordfishing. They live near the bottom in the day and 1600 feet is a good depth for them. There is a three knot current so it requires a 10 to 12 pound weight to keep the bait down near the bottom. The only way you can fish at that depth is with an electric reel.

It is a fairly complex process but once a fish is on the hook the reel does all the work to bring the fish to the surface. At that point with a fish of any real size, say two or three hundred pounds or more you need to harpoon the fish and he pulls a big float around until he gets to tired to fight much. At that point you can pull him near the boat and put a tail rope on the fish and drag him backwards to kill him or he may go crazy and kill you.

Swordfish have killed a few people doing this...so it is big game hunting for sure. Everyone I know loves to eat swordfish. I am lucky to get my share...lol

It probably sounds barberic to some people because they only see the swordfish pieces in the store or at the restaurant. Now you know.

Billy
I finally got the amp to work, well sort of. The JFET buffer circuit is still not working and I have not received the new JFETs I ordered from Mouser.

My impression of all this is that it reminds me of making jewelry. Everything is tiny and there are different requirements for soldering skills. Solid state does not lend itself to being built on eyelet boards or turret boards or even perf boards for that matter.

Discrete components can be used without much issue but op-amps and ICs need PCBs.

You need some cost effective way to build one off PCBs. One would also need some design skills to prevent unwanted coupling and other things involved with PCB design. As far as I know one off boards are pretty pricy.

The first mistake I made was not to really studying the op-amp data sheet and really understand it. Looking at a 1/4 inch square piece of black material with some tiny legs tells you nothing. This is really different from looking at a tube amp.

Anyone could solder a DIY solid state amp together on a PCB. If it worked fine, but if it did not and you are forced to trouble shoot you would not understand how to do that without understanding what is going on at each pin and why. You need more or less the same info with tubes but it is very visual. To me tube electronics is a less trouble to understand.

I am transitioning from a builder to a designer and it is a huge leap.

Fun stuff...I think...lol



Billy
Billy - looks like you used pad-per-hole board. While not a bad choice, I personally find it much easier to use veroboard/stripboard as any horizontal connection is done for you. These are quite commonly used by DIY guitar pedal builders, myself included. Take a look at this site for some examples: http://tagboardeffects.blogspot.com/

Generally speaking though, I usually use plain copper clad board and do the iron on transfer/ferric chloride etching route for my electronics projects. I'm also looking into having some professional PCB's produced once I finish a couple things I'm currently designing.
Originally Posted By: Planobilly
I am transitioning from a builder to a designer and it is a huge leap.


I am transitioning into my 70s real soon here and talk about huge leaps.... LOL!!
Originally Posted By: Simon - PG Music
Billy - looks like you used pad-per-hole board. While not a bad choice, I personally find it much easier to use veroboard/stripboard as any horizontal connection is done for you. These are quite commonly used by DIY guitar pedal builders, myself included. Take a look at this site for some examples: http://tagboardeffects.blogspot.com/

Generally speaking though, I usually use plain copper clad board and do the iron on transfer/ferric chloride etching route for my electronics projects. I'm also looking into having some professional PCB's produced once I finish a couple things I'm currently designing.


Thanks Simon

I will take a look at the material you are talking about and order some to give it a try. The last board I used worked well for the op-amp. I had to solder jump between some of the holes because they were to small to fit more than two things in one hole. That is difficult and requires precise soldering technique to do...not so easy and yes I know how but it is a PITB.

I made some experimental PCBs a long time ago with acid etching which was a lot of work and nasty chemicals to deal with.

I have a small CNC milling machine that I could easily cut through a copper clad board with extreme precision. The programing for that is also a PITB...lol

I know Gcode well but...

Anyway we should keep in contact about the PCB issues.

Thanks,

Billy
Originally Posted By: eddie1261
Originally Posted By: Planobilly
I am transitioning from a builder to a designer and it is a huge leap.


I am transitioning into my 70s real soon here and talk about huge leaps.... LOL!!


You I will deal with in a bit...lol
Billy
Originally Posted By: Planobilly
I will take a look at the material you are talking about and order some to give it a try. The last board I used worked well for the op-amp. I had to solder jump between some of the holes because they were to small to fit more than two things in one hole. That is difficult and requires precise soldering technique to do...not so easy and yes I know how but it is a PITB.

I made some experimental PCBs a long time ago with acid etching which was a lot of work and nasty chemicals to deal with.

I have a small CNC milling machine that I could easily cut through a copper clad board with extreme precision. The programing for that is also a PITB...lol

I know Gcode well but...

Anyway we should keep in contact about the PCB issues.

Thanks,

Billy


Stripboard is great, because you never have to put two leads in one hole. I do agree that using ferric chloride is kinda nasty, since it'll stain everything it touches (including skin), but with a little care it's quite easy. I'd absolutely prefer a CNC mill for it though!


Originally Posted By: eddie1261
I am transitioning into my 70s real soon here and talk about huge leaps.... LOL!!


It's often not possible for people in their 70's to perform huge leaps, maybe stick to smaller hops grin
The JFETs I ordered came this afternoon. I got an email saying they tried to deliver but no one was home. I wonder who they thought the two cars in the driveway belong to. I live in a third world country called Miami...lol This is the first time FedeX has screw up anything.

THe JFET test equipment that I ordered arrived two days ago at the wrong post office near here and was sent back to the main sorting station. I went to the post office and they said it may show up at their post office tomorrow, then in a day or two they will give it to the postman who has lost four out of the last nine packages that got shipped through USPS.

I ordered a one pound roll of solder from DigiKey. $44.00 for a pound of solder.

So I am in the process of starting to commence to begin to hurry up and sit here...lol

Billy
Well, finally after three attempts I got this to work properly.

The problem from day one was counterfeit transistors. They were marked as JFETs but they were NPN transistors As soon as I put a JFET in from Mouser everything started working as normal.

This last iteration I built on a PCB. Now I can go back and make the other iterations work. What a PITB!!



The CD player is playing Big Joe Turner through the amp. "Let the midnight special shine it light on me"



Counter fit parts....what a concept. I have been told there are a thousand silk screen people willing to put any number you want on a transistor.

Billy
Good one. I knew you'd get there in the end, and yes, from our earlier discussions, that JFET was always the suspect.
I got a new tester that has been a big help. Was able to test all the caps on Eddies radio.

I was surprised how far out of value they can be and still work. I have a ton of ceramic caps but they are only separated into little plastic bags. Trying to read the numbers even under a microscope is not easy.

The ceramic caps I use in tube stuff are about the size of a penny or bigger.

Billy
Caps are often rated with +20%/-50% tolerance, so if you have a 100μF cap it could be anywhere from 50μF to 120μF with that type of tolerance. Often they're much closer than that, but +20/-50 is not uncommon.
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