[Hey_Its_Cole]

I have a rockhopper m3 and am wanting to experiment with opamp rolling. Can some one point me in the right direction as to what to try? I tried searching but wasa not coming up with much related to the m3. I am wanting to just buy a bunch and try them out. What do they run money wise? Thanks.

 

[Andrea]

I would first try the AD843, and certainly the OPA627 too (unless you already have them in your M3). Unfortunately these are not exactly among the cheapest.

 

[Hey_Its_Cole]

Forgive my newbishness but where can I get them? From my google search results it look as if there are different pen types. Tp tell what my m3 has, do i just open the case and read the numbers on the op amps?

 

[dmb367]

Cole -

It already has the AD843 installed. I would try the AD8065, AD8610 and TI OPA627. You can get free samples of both AD chips from their site, but I think you need to mount them on Browndog adapters.

Joe

 

[dmb367]

Heres a couple good links too:

http://tangentsoft.net/audio/opamps.html

http://www.amb.org/audio/mmm/

 

[Hey_Its_Cole]

Thank you!

 

[n_maher]

You should also check the DIY forum as there are a couple of similar threads on the first page there as well.

HTH,

Nate

 

[adhoc]

you would want to find chips in the DIP8 package. the opa627 comes in DIP8.

otherwise, most of the AD opamps mentioned so far come in SOIC-8 packages which you need to solder onto a browndog adaptor. this is no simple task for someone who does not have any experience soldering SMD.

 

[jsr]

Quote:

Originally Posted by dmb367 Cole - It already has the AD843 installed. I would try the AD8065, AD8610 and TI OPA627. You can get free samples of both AD chips from their site, but I think you need to mount them on Browndog adapters. Joe

Hello Joe,

where did you get your free samples from? I'm trying to get free samples of the OPA627AP, but it seems that digi-key who is distributing TI's chips is charging for that.
Any tip?

Thanx

 

[dmb367]

Quote:

Originally Posted by jsr Hello Joe, where did you get your free samples from? I'm trying to get free samples of the OPA627AP, but it seems that digi-key who is distributing TI's chips is charging for that. Any tip? Thanx

Heres a link to the Analog Devies Page

http://www.analog.com/

the AD843, 8065 and 8610 can be ordered from there, but they only give you two free samples. TI's chips are more expensive, so I dont think you can get any for free.

PS I have pairs of 8065 and 8610 opamps, which I have no use for. If anyone wants them, I'll give them to you.

 

[jsr]

Quote:

Originally Posted by dmb367 Heres a link to the Analog Devies Page http://www.analog.com/ the AD843, 8065 and 8610 can be ordered from there, but they only give you two free samples. TI's chips are more expensive, so I dont think you can get any for free. PS I have pairs of 8065 and 8610 opamps, which I have no use for. If anyone wants them, I'll give them to you.

thanks for the info.

I'd be interested by the 8610 if you don't need it.

 

[adhoc]

Quote:

Originally Posted by jsr Hello Joe, where did you get your free samples from? I'm trying to get free samples of the OPA627AP, but it seems that digi-key who is distributing TI's chips is charging for that. Any tip? Thanx

TI has stopped distributing free samples because of freeloaders like you.

As a result its a lot more hassle for genuine electronics students, EEs or designers to get their hands on samples - people who the sampling program was originally set up for.

 

[jsr]

Quote:

Originally Posted by adhoc TI has stopped distributing free samples because of freeloaders like you. As a result its a lot more hassle for genuine electronics students, EEs or designers to get their hands on samples - people who the sampling program was originally set up for.

Hello Adhoc,

with all respect due to you, I'm not sure I understand what your problem is.
Why would you qualify me as a "freeloader" ? I'm not trying and not even expecting to have everything for free (ask my wallet how it feels these days!), but when I can find a way to get a good deal, ultimately free stuff, I won't hesitate...

Also, fyi, I've never rolled amps in the past, that's something I'm discovering, and I don't see the harm I do to the EE and students community by willing to try something new, which I'm not even sure I'll continue... So, as far as I'm concerned that fits the "evaluation" criteria for asking a free sample.

cheers

 

[jar]

Quote:

Originally Posted by jsr So, as far as I'm concerned that fits the "evaluation" criteria for asking a free sample.

The difference is, if an EE in industry uses some samples that end up in a product design, this leads to sales of thousands (or even millions) of parts in the future. That's the reason the manufacturers have sample programs.

That said, I see nothing wrong with getting samples if the manufacturer is OK with it. TI has stopped offering samples on the web, because they've decided it's not OK. If I called up my TI sales rep, I'm pretty sure whatever samples I wanted would be on their way.

 

[jsr]

Quote:

Originally Posted by jar The difference is, if an EE in industry uses some samples that end up in a product design, this leads to sales of thousands (or even millions) of parts in the future. That's the reason the manufacturers have sample programs.

good point, I must agree. But I'd comment and say that even if it doesn't necessarily lead to thousands od parts sales, it's also good free publicity for them when people discuss and give a favorable opinion of their parts. That might then encourage some designers to consider using their chips. Also, I doubt that there are millions of people asking for samples... so let's put things in perspective.

Quote:

That said, I see nothing wrong with getting samples if the manufacturer is OK with it. TI has stopped offering samples on the web, because they've decided it's not OK. If I called up my TI sales rep, I'm pretty sure whatever samples I wanted would be on their way.

I agree on that too, I never claimed that the manufacturers must agree to give free samples. But if the possibility exists and they are okay with giving samples, I won't decline...

jsr