This video was inspired by a request from a viewer for a shop-workbench tour. I considered how I would like to see equivalent videos from fellow audio/RF enthusiasts and decided to provide a quick tour. I hope to see others do the same.
Using multiple resistors in parallel does have the advantage of lowering the inductance of the whole unit as inductance behaves like resistance in parallel and series circuits. Even the large wire wound resistors have inductance in the 40 uH range and that does not cause any issues. When you get your load resistors complete, please post it on YT. I am sure many people would love to see it.
I don't use heat sink compound as it is messy and I don't see it as necessary. The bigger the heat sink the better. I have considered putting a thermal switch and a fan on mine - probably not necessary and fans do make noise. Thanks for the comments.
Fortunately, very few problems at audio frequencies. The input of everything is 1 Meg so it still ends up 200K or so. I do have to be careful not to turn on the 50 ohm terminators in the 485 scope. All the loads and cables tend to raise the output of the SG505's from 8 ppm to 40 or so ppm - but I can live with that. Thanks for your comments
For low wattage amps, it would not hurt them to put 16 ohms on an 8 ohm tap but for correct power and THD readings, the correct impedance should be used. I had some of the flat 8 ohm load resistors but the resistance varies greatly with temperature and the large WW resistors are OK - small amount of inductance that it does not matter - I used them for years. Spreading the load over multiple resistors is OK but you still only have the power dissipation that they all add up to.
I know I'm late to the party, but I did enjoy the tour very much. I suggest you replace the air conditioner with a ductless mini split unit.... they are more pricey than window units but extremely quiet, easy to install, highly efficient.... and unlike most modern window units, if you have a power outage, when the power comes back on, they come back on running instead of you having to manually reset them. Your wife will like the lower power usage, you will like the safety factor and your you tube viewers will like the quietness.
Good suggestion - I am thinking about exactly what you speak of for my apartment "backhouse", as I call it, that is next to my little shop. I do agree that the extra bit of money will be well returned on efficiency and lower electric bills (by electric bill is around $650/month in the summer)... and a quieter place to make videos. It just may come true this fall for the backhouse and shop.
Hi Glenn - my shop is a wee bit too small but that makes me work quickly when stuff comes in as it must go out quickly - I never show where the real BB gun is - HI - my camera is a Leica V-Lux 3 - I have had Nikons for all my life but the point and shoot Leica focuses so much faster and better, just so easy to use and can be fully manual also - I highly recommend it and it costs less than many Nikons - thanks for the email and glad the YT video made sense - I want to see your shop - 73 David
Grounding the metal parts of the workbench was an attempt to reduce electrical noise induced into equipment on the bench. Not sure it made a lot of difference - maybe, in some cases, I created a shock-hazard for myself. Thanks for the comments.
When the big mainframe computers went away at WSMR, I was able to buy the big green parts cabinet and two nice eleven drawer cabinets and pretty much the entire office of Unisys in El Paso and WSMR, including test equipment who I worked for, in preparation for a MSS (maintenance service supplier) contract. I did not take the MSS but sold some of it back to the company that did get the contract - so made money and got lots of stuff - worked out good for me.
FANTASTIC! Great to know you are out there. I am paying attentions. Why a conductive bench top? Why not wood or non conductive? You have inspired me to get busy organizing my work spaces much better.
I made the BNC box and do not have any significant noise problem with it. It raised the best of the SG505 from 0.0008% to usually around 0.004% or so but their could be other factors also. I have 1 meg ohm resistors in series with two of the BNC connectors so that I get a 2:1 division (reduction) in voltage into the 1 meg ohm inputs of the freq counter and such so I don't exceed their maximum rating.
Awesome shop video!!! I wish that I had known about you when I played guitar! I had found an old sears silvertone amp head at the dump, and needed it repaired. What a great you tube channel!!!!
Hi David- I am sure it's going to be a lot of help in your biz. There is a heat adjust on the handle via small pot. I cranked it all the way up for R 390A modules and heavy P2P work.. The tips come in clogged with solder but after warm up the 808 will suck in. I use the 1,8mm tip for P2P stuff, they have tips up to at least 2.0mm. I will be interested in hearing your report. Oh, I cost you less money than your wife did with the AC pwr Hi hi. vry 73 Glenn
Yes, I have been meaning to write you about it - it is very nice and I use is often. I wish it had a holder (I use an old Weller soldering iron holder) and a light (LED) on it so I can see that it is power on and hot - otherwise, it works great - thanks for the recommendation - PS - I am on 20 meters a lot lately around 14.250 MHz - if you get on sometime, maybe we can hook up. 73
Glenn - well, I ordered the Hakko 808 and told my wife it was your fault so she may be coming for you... LOL Seriously, looked like a good product - thank you so much for the suggestion - after I use it for a while I will let you know what I think of it - 73, David
half the weight of the Weller. It has a long narrow neck and can get down on tube sockets, terml strips, connectors and other P2P stuff. The 808 has it's own small vacuum pump on the handle and BOY DOES IT SUCK I don't think I will have to use wick any longer. There are YT videos on the 808 and everyone seem to say only good things. BTW I chuckled at the story about your wife turning off your AC. I wonder if she is related to my wife... HI You can't shoot em but sometimes it does cross my mind
David, You showed a BNC distribution box to feed your signals. Was this something you made, or did you purchase it buy it? Any issues with signals getting noise? Thanks
Glenn - I will check out the Hakko 808 - thanks for the info - my first name is Raymond but I usually go by my middle name, David - it is not a problem - I also answer to Ray.- and, yes, save 5 cents in electricity and cost me $400 for another scope - that' the way wife's help us save money -
Hi David- Did you get to test your Hakko desolder unit yet? I use mine at least 3 or 4 times every day and it's holding up perfectly.. I did see an Asian knock off unit that looks the same @~$100 but I don't know about he quality.. 73, Glenn
Great stuff, thanks for taking the time. Is there a way you could post or send me the link to the "chips" guy I can't find him on the bay and I'm looking for my first spectrum analyzer. Unless you would like to part with that pretty 3580, or if you could make any recommendations, I'm looking to use it on 10 and 11 meter radio. I do agree, my wife never had enough shoes.
Here is a link to a current selling produce on Ebay from Tektronix listed as "Chipxs" www.ebay.com/itm/Tektronix-RSA3408A-Real-Time-Spectrum-Analyzer-14-Day-Warranty-/162238070893?hash=item25c624806d:g:ei8AAOSwxKtX~9F- A spectrum analyzer for 30 MHz should be fairly easy to find and not cost too much. The HP 3580A is for audio and goes from 5 Hz to 50 KHz. Nowadays, the inexpensive and sometimes free FFT programs that run on your PC will actually give you better results than the 1980's HP 3580A that cost over $17K back then... Check out ARTA and SpectraPlus software for your PC to do audio work. All you need in addition to the PC and software is a cheap USB sound card. Good luck with your projects and thanks for your comments.
Hi David, I thought your name is ray for some reason.. Sorry about that. Hey, I want to spend some of your money and you will appreciate it..Back in the 80's I started using AirVac desoldering guns and they are perfect for PCB work but the Y head will not allow close point to point work. So, I did some investigation work to see if I could find something. Check out the Hakko 808 desoldering tool. It's around $200 and looks like an old Weller soldering gun we used years ago but it's about MORE>
I agree but nowadays we can have a $100,000, 1980 lab for $3 or 4 thousand and if we are lucky and get equipment that has been taken care of, we can make measurements better than 1% accuracy. I have so much confidence in the General Radio equipment, I use it to check out the new digital equipment made in foreign countries as I trust the GR equipment the most.
Hi Ray, Thanks for the tour of your Lab.. Is there room for you??? Hi hi Hey, everything in Texas is supposed to be bigger??? Where is your shop BAZOOKA?? BB gun in TEXAS?? Isn't against the LAW?? Or did you just keep the real goodies out of view??? Seriously, what camera are you using? I really need to make some videos too but haven't invested in the gear yet. Great use of your space and that gave me a few idea for my shop. Take care vry 73, Glenn WA4AOS dit dit
May you live to be a THOUSAND years old in order to continue to use that wonderful equipment. Remind your wife - she's replaceable, much of that equipment is not. :)
Impossible..... Is it possible to have too many vacuum tubes? Can a woman have too many shoes and purses? Can a shooter have too many bullets? Can a banker have too much money? The only thing I don't have enough of is room in my shop - and time left on Planet Earth - Thanks for viewing and commenting.
ElPaso TubeAmps ha ha ok i'll give u that ! So basically you fix what? Can you give some examples, I am assuming you fix big music amps, musical instruments, mixers etc, what else? what you mean by RF Radio Frequency stuff ...
Please go slower I love learning from you but for us dumbass guys you do not show how things hook up...VOM on live amps ect Thanks so much I can watch your videos all day
Really interesting video, thanks for making it. Do you not have any problems with loading etc when paralleling all those test equipment inputs or are there fewer problems at audio frequencies?
