SVCO and VCLFO tempco , a lesson learnt and question

Discussion and support for users and builders of Oakley Sound musical products.

Moderators: Kent, Synthbuilder

Post Reply
User avatar
Pav
Wiggling with Experience
Posts: 311
Joined: Sat Mar 19, 2016 3:21 pm
Location: UK Hampshire

SVCO and VCLFO tempco , a lesson learnt and question

Post by Pav » Tue Oct 31, 2017 2:17 pm

How a well known uk parts provider thought putting 6 14pin PIC chips in an antistatic bag clearly labelled for 7 8pin LT1013CP might cheer me up I dont know :mad: ..but thats another story.
[EDIT - called them and they resent the correct parts next day = excellent service -Pav]

This is my cock-up but it may help others ...

I built the VC-LFO before i was able to complete the SVCO-B...waiting for sock6..which just arrived :nana:

I had ordered the correct number and type of tempco resistors to complete the build. :yay:

The KRL 1K 3500ppm black ones used by the VCOs and the smaller "Akaneohm" 1k 1% 3000ppm/K used by VRG et al.

The VC-LFO picture in the webpage, user and build guides of VC-LFO clearly shows a KRL 3500 black one...so i used my last one.
It works fine. :hail:

When it came to the SVCO finishing.. I had only the smaller 3000 tempco left...and its leads do not fit over the IC plus socket. :bang:

When i re-read the parts listed in the bg for VC-LFO I can now see it says 3000 and the position of the holes now makes sense. :doh:

But the photos threw me. :despair: Thats the lesson...its easy to get seduced by the photos but they are not what we old computer folk call the "system of truth" ..its the parts list in the build guide.

My question now is will a 2K 3500ppm work - I only have a 2K KRL in my parts box.? Worth asking? :help:
Last edited by Pav on Thu Nov 02, 2017 8:44 am, edited 1 time in total.
rgds Pav

User avatar
Synthbuilder
Super Deluxe Wiggler
Posts: 3024
Joined: Tue Mar 24, 2009 9:12 am
Location: Cumbria, UK

Re: SVCO and VCLFO tempco , a lesson learnt and question

Post by Synthbuilder » Wed Nov 01, 2017 4:31 am

Pav wrote:But the photos threw me.
In fairness the description under the close up photograph in the Builder's Guide notes that you can use either the +3500ppm or the smaller +3000ppm device. The +3000ppm devices being recommended because they are cheaper and are adequate for VC-LFO duties. The +3500ppm will give more stability and could be useful when using the VC-LFO as an audio oscillator.
My question now is will a 2K 3500ppm work - I only have a 2K KRL in my parts box.?
2K should work if you make R34 a 75K resistor.

Tony

User avatar
Pav
Wiggling with Experience
Posts: 311
Joined: Sat Mar 19, 2016 3:21 pm
Location: UK Hampshire

Post by Pav » Wed Nov 01, 2017 7:36 am

Re : In fairness the description under the close up ...

My fault entirely. No offense intended. Thanks for the 75k resistor tip.
Listing the KRL as an option on the pricing would tie the picture in .. just a thought.
rgds Pav

User avatar
Synthbuilder
Super Deluxe Wiggler
Posts: 3024
Joined: Tue Mar 24, 2009 9:12 am
Location: Cumbria, UK

Post by Synthbuilder » Wed Nov 01, 2017 8:55 am

Pav wrote:Listing the KRL as an option on the pricing would tie the picture in .. just a thought.
I had that when the board first came out and what happened was people wanted to buy both. :deadbanana:

I'll try again though. I'm always happy to sell people stuff. :hihi:

Tony

User avatar
Pav
Wiggling with Experience
Posts: 311
Joined: Sat Mar 19, 2016 3:21 pm
Location: UK Hampshire

Post by Pav » Wed Nov 01, 2017 11:01 am

Ill stop suggesting stuff, you have been doing this longer than me :hyper:
rgds Pav

Post Reply

Return to “Oakley Sound Systems”