SMT parts for PINT

[heady 0]

Anyone ordered/ordering PINT PCB from Tangent? I looked at Farnell and at RS but cannot find all the required SMT parts. RS has many chip resistors but unfortunately not some which is required. Also required capacitors and diodes in the tiny little bits.

 

So... I am contemplating buying these tiny parts from Mouser in USA. I am thinking of asking a friend in the US to order, pay and then post the package to me.

 

Anyone out there interested? Let me know. Please note that I will not be able to control the time the package takes to come to SG from US, so if you are in a hurry, don't join me.

 

I like my Pimeta very much but the one I have isn't portable enough for me. I am hoping the Pint will be as good and yet portable.

 

[squalle 0]

Ermm

 

one guy has requested me to assemble a PINT for him

so if you want, maybe we joint order then also abt the resistors, not necessary to follow the same values

e.g. dun you find the gain is rather large? especially when u're using a pair of somehow efficient CK7.

I'm thinking to drop it to 2.5 or 3

 

the diodes are not necessary unless you really want the on-board charging, which IMO, not really as robust as those stand alone charger.

 

so I'd suggest parts we get from local farnell, but get the PINT + vol pot from tangent

wat do u think?

 

let's see who else wanna join

[Zephyron 0]

That's me, but I dunno what to do o.O

*is blur*

[heady 0]

Ermm

 

one guy has requested me to assemble a PINT for him

so if you want, maybe we joint order then also abt the resistors, not necessary to follow the same values

e.g. dun you find the gain is rather large? especially when u're using a pair of somehow efficient CK7.

I'm thinking to drop it to 2.5 or 3

 

the diodes are not necessary unless you really want the on-board charging, which IMO, not really as robust as those stand alone charger. 

 

so I'd suggest parts we get from local farnell, but get the PINT + vol pot from tangent

wat do u think?

 

let's see who else wanna join

I ordered the PCBs (2xPint and 2xTread) and opamps last week and should be getting them this week, I hope. Tangent is normally very prompt. I still have a number of the volume pot as I bought 10 from him last time and used up about half.

 

Farnell don't have the SMT parts unless I didn't search the right way. RS do have some of them but after I found they don't have the 620K resistor, I didn't bother to look for the other parts. So, I only need the smt parts. Can we get them in SG?

 

I agreed the gain is a bit too much for the IEMs. But tangent seems to imply better not to change the values around too much, I am no EE guy, my major is in biology.

 

If any one can work out the math and make recommendations, I can run it past tangent to see what he says.

 

Edit - I just check the site and used the values given in the gain calculator and the gain is 2.2 which is ok for IEMs. I used gain of 6 in my Pimeta and still can use it with my CK7 although only the first few degrees of turn only.

Edited March 28, 2006 by heady

[squalle 0]

hmm

 

how do you get to ur 2.2 value?

it's 620k and 120k R arent they?

 

you've got 10! LOL

so many of them

is there really no other source of such alps pot but to get from him?

 

I've worked out the feedback R values to get a gain of 2.5

you might've read the spec sheet of AD8397, the minimum gain is stated as 2, hence the 2.5

then you ought to balance the R seen by the op-amps at the + and - input pins

well, they should be 140kR and 350kR, but farnell has no such values. so replace them with nearest values, 150k and 360k.

after re-calculation, they're still OK, i.e. around the intended design parameters (gain of 2.5 and equivalent resistance of 100k)

[heady 0]

hmm

 

how do you get to ur 2.2 value?

it's 620k and 120k R arent they?

 

you've got 10! LOL

so many of them

is there really no other source of such alps pot but to get from him?

 

I've worked out the feedback R values to get a gain of 2.5

you might've read the spec sheet of AD8397, the minimum gain is stated as 2, hence the 2.5

then you ought to balance the R seen by the op-amps at the + and - input pins

well, they should be 140kR and 350kR, but farnell has no such values.  so replace them with nearest values, 150k and 360k.

after re-calculation, they're still OK, i.e. around the intended design parameters (gain of 2.5 and equivalent resistance of 100k)

 

Sorry ah, the gain calculation, used the wrong values. You are right, it is gain of 6. Thanks for pointing out my error. I told you I am no electronic person, only like music.

 

Got about 5 of the pot left, they got switch built-in. Can't find in SG.

 

I am all for joining you to buy the parts here in SG. Let me know the parts number and I will call Farnell and collect them. Farnell is just around the corner from my office.

 

 

Edited March 29, 2006 by heady

[squalle 0]

parts ordered from farnell

 

will be delivered to my office btw

[heady 0]

squalle, you ordered already? Wow. that's fast. Can you send me list of the parts and the farnell # for the pasts. I couldn't find the necessary parts from farnell, my bad. Thanks.

[squalle 0]

are you sure u wanna buy those resistors on ur own order?

hmm, I was actually thinking that you would wanna share some off me? haha

coz min number of resistors are like 50

 

but if you insist, I'll post later

 

PS: some of the parts will only arrive tomorrow, where others will be in 3-4 working days

Farnell really screwed up

they cant even deliver today ... sigh.... I've got 1 item that I wanna assemble tonight, but stupid farnell screwed up my plan.....

oh yea, and their availability status is always screwed up.

[Kippei 0]

yea ... i order from farnell also same thing... 80% of the stuff are located overseas...

[heady 0]

are you sure u wanna buy those resistors on ur own order?

hmm, I was actually thinking that you would wanna share some off me? haha

coz min number of resistors are like 50

 

but if you insist, I'll post later

 

PS: some of the parts will only arrive tomorrow, where others will be in 3-4 working days

Farnell really screwed up

they cant even deliver today ... sigh.... I've got 1 item that I wanna assemble tonight, but stupid farnell screwed up my plan.....

oh yea, and their availability status is always screwed up.

squalle - yup, I found out how to locate the tiny resistors and found out they come in packs of 50s. Wow. Need a few and end up buying so many. SO.... I will buy from you those that you can spare. I will buy only those values you don't have.

 

I am thinking of following headfi's amb's values for R3 and R4 for a gain of 4 or 3.

 

Can you pm me the values you got? Also did you order the tiny caps as well?

 

Thanks and I hope you are located in the east or at least the south.

 

Can't wait to do up the board and try the sound.

 

 

[squalle 0]

I sure can spare LOL

 

as I've told you, the gain that I plan is 2.5. 150k and 330k

so you wanna use my values or follow amb's?

 

I've tried AD8397. it's b*tchy

but the sound's nice. very strong chip. by itself, the current output can rival that of BUF634

anyway, I've got the ferrite too, and also the 10pF multi-layer ceramic cap (NP0)

that one is to prevent oscillation, together with the ferrite

 

btw. i'm at west end LOL

I'll bring some parts to you tomorrow, meet me at PS. how abt that?

 

tangent's sent my boards and they're on their way to sg

 

 

[heady 0]

I am thinking of following amb's values as what he said made sense to me. (as if I know anything... ) I will try amb's values first and if no good then I will try yours. I am just too itchy...

 

So I will get the resistors from Farnell if they have them. What about the other parts besides the chip ferrites and the ceramic caps. Still got to get the 0.1uF ceramic, 1.5uF and 4.7uF tantalum caps. Or are you substituting something else for them too.

 

I can get 12 pcs of the chip ferrite and 8 pcs of the 10pF ceramic cap from you. BTW where and what is PS? Sorry, swa-gu here. If you go to AnythingAudio at Parklane, I can arrange with Albert to collect on my behalf.

 

 

[squalle 0]

all have LOL

just that I forgot to type them out

 

12 pcs ferrite? so many?

you only need 3 for each board leh

 

PS == plaza singapura

[heady 0]

all have LOL

just that I forgot to type them out

 

12 pcs ferrite? so many?

you only need 3 for each board leh

 

PS == plaza singapura

You know SG = kiasu thought just in case friend ask me to build for them. It always happens when I show them my amps.

 

Ok, can get 4 sets of everything? I work near Plaza Singapura on Fridays, so can meet you there or if it is convenient for you to walk to Anything Audio, I can ask Albert to help collect them from you. You can then listen to his extensive Beyer collection.

 

Please PM me the costs of every thing. Thanks squalle.