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I am trying to figure out the Pin: 1 location on the Digital Filter IC: LTC1569-7 for a System Blue build. There is no point at one corner of the housing. See image below. Could someone help identify the Pin: 1 location. Thank you and appreciate it.

[attachment=2464]
(2016-06-18, 13:00)rwhalb@verizon.net Wrote: [ -> ]I am trying to figure out the Pin: 1 location on the Digital Filter IC: LTC1569-7 for a System Blue build. There is no point at one corner of the housing. See image below. Could someone help identify the Pin: 1 location. Thank you and appreciate it.

By the datasheet, it should have a wedge along one side - that side is pins 1-4 (counter-clockwise), the other side is 5-8.
(2016-06-18, 13:19)Shadow Panther Wrote: [ -> ]
(2016-06-18, 13:00)rwhalb@verizon.net Wrote: [ -> ]I am trying to figure out the Pin: 1 location on the Digital Filter IC: LTC1569-7 for a System Blue build. There is no point at one corner of the housing. See image below. Could someone help identify the Pin: 1 location. Thank you and appreciate it.

By the datasheet, it should have a wedge along one side - that side is pins 1-4 (counter-clockwise), the other side is 5-8.

So from the image above would you agree that wedge is on the left side and Pin: 1 is in the upper left-hand corner?
(2016-06-18, 13:33)rwhalb@verizon.net Wrote: [ -> ]
(2016-06-18, 13:19)Shadow Panther Wrote: [ -> ]
(2016-06-18, 13:00)rwhalb@verizon.net Wrote: [ -> ]I am trying to figure out the Pin: 1 location on the Digital Filter IC: LTC1569-7 for a System Blue build. There is no point at one corner of the housing. See image below. Could someone help identify the Pin: 1 location. Thank you and appreciate it.

By the datasheet, it should have a wedge along one side - that side is pins 1-4 (counter-clockwise), the other side is 5-8.

So from the image above would you agree that wedge is on the left side and Pin: 1 is in the upper left-hand corner?

Yes, it seems so.
Pardon me for butting in, but reading about BLUE construction I'm interested.

Is this photo taken from the bottom of the chip with the little pins projecting up towards the viewer, or is the perspective such that the feet ar actually down towards the surface it is resting on? 

For some reason as I look at the chip it looks like it was placed flat surface down with the legs up towards the camera.

That would make a heck of a difference, too.

Just asking before you solder expensive stuff to a hard to remove spot.

Dale
(2016-06-18, 15:23)Dale.Reid Wrote: [ -> ]Pardon me for butting in, but reading about BLUE construction I'm interested.

Is this photo taken from the bottom of the chip with the little pins projecting up towards the viewer, or is the perspective such that the feet ar actually down towards the surface it is resting on? 

For some reason as I look at the chip it looks like it was placed flat surface down with the legs up towards the camera.

That would make a heck of a difference, too.

Just asking before you solder expensive stuff to a hard to remove spot.

Dale

Dale:

Thanks for your interest. The photo is taken from the top of the chip. I used by Samsung Galaxy S5 using a magnifier app. The legs are down away from the camera.

Do you agree then that Pin: 1 is in the upper left-hand corner?

---Ron
...............
All true. The "chamfer" edge is the 1-4 pin side. It is on the datasheet for the part at http://cds.linear.com/docs/en/datasheet/15697fs.pdf. The first page has the pin diagram where the gray area is the pin 1-4 side. There is also a drawing near the end of the datasheet.

The manufacturer's datasheets are the best source for information on a part. Most are available free if you know where to find them.

99% of the time, the laser etched markings are on the top side of the part.

Greg
sorry for squeezing in to this post too

but how do i know, that i should solder the digital filters on the board or not.
is it depending of the noise-level? but how do i measure it? and what is the max level of it?

thanx a lot
Patrick
Hello Patrick,

The digital filters option is mainly used to cut the signal above a certain frequency which disturbs a lot the detector.
This can be very usefull to get rid of LF emitters such a military radio or so.

Without your station up and running this is difficult to give you a better diagnosis.

Note that the noise can be reduced by grounding the controller to i.e. a cold water pipe and by using a clean and "silent" power supply.
Hello Delande
my station is up and running since 2 days Smile
and i guess i have too high noises and have to make some improovments. but which one Huh
in a few day i'll get the Voltage regulator extension for the PCB-21 - dont know if that will decrease my noise-Level or not.

my actual settins are like in the picture below:
on Channel A i have 36 - 66 mVpp
on Channel B i have 17 - 24 mVpp
on Channel C i had 13 - 14 mVpp - but this morning i had 320 - 440mVpp so that i decrased the Gain till i had 15 - 20 mVpp.. in this case the noise is variable..
are those levels high? or ok?

but sure i'll ground the controller and hope the noise will go down.
my power-supply is quite normal and i think it isnt that "clean and silent". could you recomand me a clean and silent one?

thx a lot
Patrick
(2016-07-20, 10:57)Patrick Wrote: [ -> ]Hello Delande
my station is up and running since 2 days Smile
and i guess i have too high noises and have to make some improovments. but which one Huh
in a few day i'll get the Voltage regulator extension for the PCB-21 - dont know if that will decrease my noise-Level or not.

my actual settins are like in the picture below:
on Channel A i have 36 - 66 mVpp
on Channel B i have 17 - 24 mVpp
on Channel C i had 13 - 14 mVpp - but this morning i had 320 - 440mVpp so that i decrased the Gain till i had 15 - 20 mVpp.. in this case the noise is variable..
are those levels high? or ok?

but sure i'll ground the controller and hope the noise will go down.
my power-supply is quite normal and i think it isnt that "clean and silent". could you recomand me a clean and silent one?

thx a lot
Patrick

Show us a screenshot of your signal graph. Let's see what sort of noise you've got. Apple power supplies, especially the 2.4A, are nice.
The voltage regulator extension will most likely not improve the noise levels.
Where do you keep your station?
now i groundet the controller by using a 240V power point - but almost nothing changed.
i also changed the power supplies with the one from my iPad - it seemed to be even worst - so i changed it back to the one i used before.

the antenna 3x20cm ferrite is in the garden, 10m from the house an the controller is on the terrasse which is covered whit glas. near the controller is a 240V power point and a weather-station from oregon scientific Systems.

in the picture my actual Settings and some signals.
thx a lot
Patrick
Today I installed the filters and jumpered J0.

The guide says you can adjust the filters, but I do not see anywhere to do this.
when the board recognises the filters it will add a menu under the amp concerned. In there you can set the cutoff frequency
Sorry for interrupt. Could anyone spot the j0 jumper on new blue(green board)?. I cant see it so far. (Or i need a new pair of glasses Tongue)
Shy ...................
Thanks Richo. I allready order a new pair of glasses.. Wink
Hello,

I added one filter IC for the E-amp channel, I soldered J0, but I don't see the extra filters menu... What am I doing wrong?
(2016-09-14, 19:18)Polyphemus Wrote: [ -> ]Hello,

I added one filter IC for the E-amp channel, I soldered J0, but I don't see the extra filters menu... What am I doing wrong?

You may have to update the firmware.

Older versions did not have filter menu.
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