The No.1 Website for Pro Audio
 All  This Thread  Reviews  Gear Database  Gear for sale     Latest  Trending
lexicon 224 dead larc
Old 8th June 2018
  #31
Lives for gear
 

Quote:
Originally Posted by rtype909 View Post
hi,
from what you say there is probably a short somewhere on the 5v rail. you need to work out where that is - it could be on any of the boards
Also ensure the earth is still connected on your 224. I did buy a 224 from the USA to fix and a tech had cut the earth.
and the earth connection is exactly what im having in mind since last night. i think i might not have a proper connection! it might come from the ribbon cable going to the remotes db25 only please help me out... where was it connected to originally?
Old 11th June 2018
  #32
Lives for gear
 

Quote:
Originally Posted by salomonander View Post
and the earth connection is exactly what im having in mind since last night. i think i might not have a proper connection! it might come from the ribbon cable going to the remotes db25 only please help me out... where was it connected to originally?
hey,
can i bump this question? im done with the basic tech work. recapped everything with fr caps, double checked all top layer connections and corrected all jumpers. actually im rather confident. but i am a bit confused about my ground connection.

analog ground and chassis ground are connected via the ribbon cable going from the xlr board to the mainframe only. is this correct?
Old 2nd July 2018
  #33
Gear Nut
 

batteries

not to hijack the thread,

but has anyone been running the 224x without the nicd batteries on the nvs card?

as far as i understand the nvs card carries some of the eproms for the extra presets, and the batteries themselves only the user presets?

since i'm not saving any of my own presets, and the batteries were just about to leak proper, i thought if it's ok to use the unit without new batteries???

many thanks,

U
Old 2nd July 2018
  #34
Lives for gear
 
Radardoug's Avatar
 

Its fine running it without batteries, you may get an error message.
There is currently a NVS board on Ebay, have a look and see what they did for batteries. Not a bad idea, the originals would always leak on the board. You can use non-rechargeables, and change them when they go flat.
Old 2nd July 2018
  #35
Lives for gear
 
Radardoug's Avatar
 

Quote:
Originally Posted by salomonander View Post
hey,
can i bump this question? im done with the basic tech work. recapped everything with fr caps, double checked all top layer connections and corrected all jumpers. actually im rather confident. but i am a bit confused about my ground connection.

analog ground and chassis ground are connected via the ribbon cable going from the xlr board to the mainframe only. is this correct?
The LARC is supplied with a.c. from the mainframe, it then rectifies and smooths this to provide its own local power. The ground then acts as a reference for the RS422 control signals. There should be no connection from the LARC to audio ground, no audio goes through the LARC. It does need a connection to digital ground.
You should check that you are getting a.c and d.c appropriately at the LARC when it is connected. If you are seeing a.c. relative to the mainframe ground on the LARC d.c. line, then you have no earth. A bit of simple measuring with an ohmmeter should tell you.
Lexicons documents reflect the way the system developed. The LARC was a later development, and only used on the 224XL. But their documents are comprehensive and pretty accurate.
Old 14th July 2018
  #36
Lives for gear
 

hey guys,
im back from the dead.... i had too much "real" work in order to proceed this further. i did power it up again and still have the same issue. although i replaced avery single cap, double checked all diodes etc.... darn

now, today i measured my power xformer. maybe im doing it wrong. but it tells me there are shorts all over the place. could this explain my issue of having big ac on my dc lines?
Old 14th July 2018
  #37
Lives for gear
 
Radardoug's Avatar
 

Does it blow a mains fuse? If not, its highly likely it is fine. Perhaps you should take it to someone who knows more about electronics.
Old 16th July 2018
  #38
Lives for gear
 

Quote:
Originally Posted by Radardoug View Post
Does it blow a mains fuse? If not, its highly likely it is fine. Perhaps you should take it to someone who knows more about electronics.
thanks man. no it doesnt burn fuses. i know i should give this to someone else but i dont have the cash. plus i pretty much narrowed it down to either the mains xformer, main filter cap or that varo711 diode. ill try the diode next.
Old 8th June 2019
  #39
Gear Nut
 
rtype909's Avatar
did you give up on this?
Topic:
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump