Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
Search
AM501 Stuff (op-amp references)
|
Kuba Ober
On Monday 05 February 2007 23:41, you wrote:
Beside collecting TM500 plugins, anyone actually usem, in particulars,Anything that has got banana jacks on it *may* perform poorly for anything above a few kilohertz due to parasitics, unless you put the feedback path next to the chip. It does have a place to solder components inside, BTW. The op-amp inside of AM501 can be replaced by a more modern chip, if you wish so. The plugin itself was designed for teaching op-amps, and has little utility beyond that methinks. For source of great op-amp circuits, download this *excellent* book: Applications Manual for Computing Amplifiers for Modeling, Measuring, Manipulating & Much Else. Then you'll want to get Troubleshooting Analog Circuits by Bob Pease, which has an excellent section on real life op-amp behavior. All in all, a good source of experimentation data is , which has tons of analog computation applications etc. Cheers, Kuba |
|
jones_chap
Thanks. You beat me to the second question! I did wanna know if I
could "upgrade" knowing that better op-amps exist. I've downloaded the book and will check it out later and added the site to my Audio & Electronics Bookmarks. Interesting note about "anything with banana plugs" is that when playing around with the AM501 plugins was a sensitivity of the output based upon the proximity of my hand near the jacks. Wild and crazy things would happen as I got anywhere near 'em, sorta. One was much more sensitive than the other. Do ya have any recommendations for a replacement. I'd even be willing to spend more than the few cents that some of these cost--maybe even like $5--15 per chip! : ) Thanks again. |
|
J Forster
From: "jones_chap" <jones_chap@...>
[snip] Interesting note about "anything with banana plugs" is that when playing around with the AM501 plugins was a sensitivity of the output based upon the proximity of my hand near the jacks. Wild and crazy things would happen as I got anywhere near 'em, sorta. One was much more sensitive than the other. The noise, etc. is capacitively coupled to your circuitry. Reduce the values of the components in the FB loop and it will go down or use a grounded aluminum foil shield. -John |
|
Johnny Chapman
Interesting note, I was using the BNC connections. I
also noted that I had some ground noise, and at really low output levels, sometimes the desired signal would be swamped by line current. But yes, I believe I sorta know what you're talking bout. I cleared some of it up by grounding the op-amp to the frame with the signal gen in it. An interesting note, I've had this problem with tubed rf alignment equipment. I solved it by swapping the ground and signal test points! I later read from a Tek measurement something or another, that it was just a kludge fix as floating the scope : ( Thanks. I hope to actually stop playing and doing more directed studying. Thanks. ____________________________________________________________________________________ Don't pick lemons. See all the new 2007 cars at Yahoo! Autos. |
|
Ashton Brown
Note that there are BNC adaptors on an extruded oval alloy shield which shrouds right down to the faceplate plane (at least hP sold these - probably others.) Wish I had a few more of these. With the shield physically connected to the black/common binding post, you have ..almost.. a fully shielded 'can'. Worked fine for the few-???V noise floors of the various sensitive good AC meters du jour.
toggle quoted message
Show quoted text
(My lovely Racal-Dana 9300, good down to Boltzmann noise and to a phenomenal MHz top-end RMS, ~20 MHz at 6:1 crest IIRC? - natch was already BNC equipped.) Very handy with it's output amp sent to an accurate DC DVM, when you care about <0.1% relative levels. Ergo "binding posts" need not be a huge handicap - anywhere near audio freq. Ashton J Forster wrote: From: "jones_chap" <jones_chap@...> |
|
Kuba Ober
On Wednesday 07 February 2007 19:05, you wrote:
Thanks. You beat me to the second question! I did wanna know if IWell, the deal is this: there's no easy way to get performance out of a better chip if you have large, uncontrolled and *variable* parasitics. That's what your hand waving is :) The way to fix it is to use your op amp in the circuit, not in the plugin. A faster op-amp may even start oscillating just from the fact that it's inside of the AM501 wiring harness. Probably the only road to improvement is to use a similarly slow op-amp, but a more DC-accurate one. The AM501 is not really useable for much beyond simple school-type experiments. It wasn't meant to be! It was specifically designed for use in educational setting AFAIK. I have lots of unused OP177 chips, if you want a few just let me know off-list. They are good replacements for 741 and friends -- similarly slow, but much more precise. Cheers, Kuba |
|
Stan and Patricia Griffiths
Hi Ashton,
You might want to watch my eBay sales for the next several weeks. I am helping a widow dispose of a HUGE estate left by a very smart Tektronix microwave engineer. Right now, we have 90 auctions on with lots of terminators, adapters, attenuators, etc. and will have lots of other stuff, too. I have seen some of those BNC/binding post ¡°cans¡± in among the other stuff and I have more than I will ever use already. When I say HUGE estate, I mean a 2500 square foot house with a full basement absolutely FULL of stuff . . . upstairs and down . . . you can barely walk around in it . . . in some cases, you can¡¯t! The stuff is packed so densely that you simply can¡¯t see all of it until some of it gets sold. Also, there are 8 storage lockers full and one of them is about the size of a 4 car garage. Some of the aisles between the shelves are packed full, too, so you can¡¯t see all of the stuff in the storage lockers either. This guy had ALL kinds of stuff. Lots of Tek. Lots of HP. Machine tools. Hand tools. Hundreds of musical instruments. thousands of books, 6 Mercedes Benz cars. One Porsche. Motorhome. Guns. Several early Edison phonographs and lots of wax cylinders. Tons of parts . . . all kinds. I will not live to see the end of this estate sale. Unfortunately, it is 40 miles from my house . . . My eBay name is w7ni. Take a look. I already sold the Bird wattmeter and a nice Tek 191, sorry. Coming soon: LC130 meter, TM501, 321A, P6015 HV probes, 109, 2710, etc. etc. Also lots of 11K mainframes and plugins and 7K, too, if I can figure out a good way to ship them. I think I¡¯ll keep the 576 . . . The widow is keeping the 492A since that was one of the engineer¡¯s projects. I think this guy was KING of the pack-rats. Stan _____ From: TekScopes@... [mailto:TekScopes@...] On Behalf Of Ashton Brown Sent: Wednesday, February 07, 2007 10:34 PM To: Tekscopes Subject: Re: [TekScopes] Re: AM501 Stuff (op-amp references) Note that there are BNC adaptors on an extruded oval alloy shield which shrouds right down to the faceplate plane (at least hP sold these - probably others.) Wish I had a few more of these. With the shield physically connected to the black/common binding post, you have ..almost.. a fully shielded 'can'. Worked fine for the few-?V noise floors of the various sensitive good AC meters du jour. (My lovely Racal-Dana 9300, good down to Boltzmann noise and to a phenomenal MHz top-end RMS, ~20 MHz at 6:1 crest IIRC? - natch was already BNC equipped.) Very handy with it's output amp sent to an accurate DC DVM, when you care about <0.1% relative levels. Ergo "binding posts" need not be a huge handicap - anywhere near audio freq. Ashton |
|
Hi Stan, It looks like the Tektronix engineer you¡¯re talking about is
toggle quoted message
Show quoted text
a huge winner of the ¡°He who dies with the most ¡°toys¡± wins!!!¡± contest¡God bless him!! Although the other part of the saying is ¡°He who dies BROKE with the most toys wins¡±¡ Sounds like he left his widow in good shape financially¡God bless him and her. Stan, I bought some Tek Blue paint today from Patricia and if this ¡°bonanza¡± of Tek antiquities that you just acquired is what it sounds like , I¡¯ll be buying more stuff!! To the Group¡. I bought some ¡°Tek Blue¡± paint from Stan and Patricia (today) and some last fall that I used to paint/ touched up about ten 400 series cabinets with INCREDIBLE results !!!. It¡¯s lacquer and it¡¯s stinky but what a job it does!!! If you have a Tek scope that you ¡°love¡± buy a can of Stan and Patricia¡¯s ¡°Tek Blue¡± ¡ highly recommended !!!! On a different subject¡ as usual, Deane Kidd comes up ¡°large ¡°again!! Who else would have a ¡°timing IC Tek # 155- 0021 xx ??? that fixes a broken 7904 so beautifully !!! What I love about Deane the most is that you E-mail him and ask him for a ¡°hen¡¯s tooth¡± and he replies with an email describing four different potential Tek part numbers and then asks ¡°what color do you want?¡± Seriously folks, we are all fortunate to have Stan and Patricia and Deane E. Kidd as invaluable resources of Tektronix knowledge and parts! Regards to all, Ron Simmons -----Original Message-----
From: TekScopes@... [mailto:TekScopes@...] On Behalf Of Stan and Patricia Griffiths Sent: Friday, February 09, 2007 10:03 PM To: 'Ashton Brown' Cc: TekScopes Subject: RE: [TekScopes] Re: AM501 Stuff (op-amp references) Hi Ashton, You might want to watch my eBay sales for the next several weeks. I am helping a widow dispose of a HUGE estate left by a very smart Tektronix microwave engineer. Right now, we have 90 auctions on with lots of terminators, adapters, attenuators, etc. and will have lots of other stuff, too. I have seen some of those BNC/binding post ¡°cans¡± in among the other stuff and I have more than I will ever use already. When I say HUGE estate, I mean a 2500 square foot house with a full basement absolutely FULL of stuff . . . upstairs and down . . . you can barely walk around in it . . . in some cases, you can¡¯t! The stuff is packed so densely that you simply can¡¯t see all of it until some of it gets sold. Also, there are 8 storage lockers full and one of them is about the size of a 4 car garage. Some of the aisles between the shelves are packed full, too, so you can¡¯t see all of the stuff in the storage lockers either. This guy had ALL kinds of stuff. Lots of Tek. Lots of HP. Machine tools. Hand tools. Hundreds of musical instruments. thousands of books, 6 Mercedes Benz cars. One Porsche. Motorhome. Guns. Several early Edison phonographs and lots of wax cylinders. Tons of parts . . . all kinds. I will not live to see the end of this estate sale. Unfortunately, it is 40 miles from my house . . . My eBay name is w7ni. Take a look. I already sold the Bird wattmeter and a nice Tek 191, sorry. Coming soon: LC130 meter, TM501, 321A, P6015 HV probes, 109, 2710, etc. etc. Also lots of 11K mainframes and plugins and 7K, too, if I can figure out a good way to ship them. I think I¡¯ll keep the 576 . . . The widow is keeping the 492A since that was one of the engineer¡¯s projects. I think this guy was KING of the pack-rats. Stan _____ From: TekScopes@yahoogrou <mailto:TekScopes%40yahoogroups.com> ps.com [mailto:TekScopes@yahoogrou <mailto:TekScopes%40yahoogroups.com> ps.com] On Behalf Of Ashton Brown Sent: Wednesday, February 07, 2007 10:34 PM To: Tekscopes Subject: Re: [TekScopes] Re: AM501 Stuff (op-amp references) Note that there are BNC adaptors on an extruded oval alloy shield which shrouds right down to the faceplate plane (at least hP sold these - probably others.) Wish I had a few more of these. With the shield physically connected to the black/common binding post, you have ..almost.. a fully shielded 'can'. Worked fine for the few-?V noise floors of the various sensitive good AC meters du jour. (My lovely Racal-Dana 9300, good down to Boltzmann noise and to a phenomenal MHz top-end RMS, ~20 MHz at 6:1 crest IIRC? - natch was already BNC equipped.) Very handy with it's output amp sent to an accurate DC DVM, when you care about <0.1% relative levels. Ergo "binding posts" need not be a huge handicap - anywhere near audio freq. Ashton [Non-text portions of this message have been removed] [Non-text portions of this message have been removed] |
|
Stan and Patricia Griffiths
Hi Larry,
toggle quoted message
Show quoted text
You might have known him. His name was Larry Lockwood. Stan -----Original Message-----
From: Larry Snyder [mailto:larrys@...] Sent: Friday, February 09, 2007 7:35 PM To: w7ni@... Subject: RE: [TekScopes] Re: AM501 Stuff (op-amp references) Stan, is this anyone whose name I might recognize from the 70's-80's? thanx, -ls- |
|
Stan and Patricia Griffiths
Hi Ron,
Thanks for the kind words. By the way, the original Tek paint is lacquer, too, and I got it from the same place Tek did . . . Stan & Patricia _____ From: Ron Simmons [mailto:RJSimmons@...] Sent: Friday, February 09, 2007 7:47 PM To: 'Stan and Patricia Griffiths'; 'Ashton Brown' Cc: 'TekScopes' Subject: RE: [TekScopes] Re: AM501 Stuff (op-amp references) Hi Stan, It looks like the Tektronix engineer you're talking about is a huge winner of the "He who dies with the most "toys" wins!!!" contest.God bless him!! Although the other part of the saying is "He who dies BROKE with the most toys wins". Sounds like he left his widow in good shape financially.God bless him and her. Stan, I bought some Tek Blue paint today from Patricia and if this "bonanza" of Tek antiquities that you just acquired is what it sounds like , I'll be buying more stuff!! To the Group.. I bought some "Tek Blue" paint from Stan and Patricia (today) and some last fall that I used to paint/ touched up about ten 400 series cabinets with INCREDIBLE results !!!. It's lacquer and it's stinky but what a job it does!!! If you have a Tek scope that you "love" buy a can of Stan and Patricia's "Tek Blue" . highly recommended !!!! On a different subject. as usual, Deane Kidd comes up "large "again!! Who else would have a "timing IC Tek # 155- 0021 xx ??? that fixes a broken 7904 so beautifully !!! What I love about Deane the most is that you E-mail him and ask him for a "hen's tooth" and he replies with an email describing four different potential Tek part numbers and then asks "what color do you want?" Seriously folks, we are all fortunate to have Stan and Patricia and Deane E. Kidd as invaluable resources of Tektronix knowledge and parts! Regards to all, Ron Simmons |
to navigate to use esc to dismiss