Denon 2805 - No Output on Right Channel (fuse problem?)

Discussion in 'AV Receivers & Amplifiers' started by sibeer, Sep 17, 2007.

Tags:
  1. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    Hi everyone,

    Posted this in the amp section as well then thought the sepcialists may be hanging out in here :) I have just bought a Denon 2805 from a seller on here and when it arrived the Right Channel has no speaker level output for either A or B front speakers (pre-amp output is fine though).

    I am just wondering whether it would be worth my while opening the thing up to have a look before trying to get a return and refund from the seller? About 15 years ago I had a similar problem with an old A&R Cambridge (or ARCAM to the young folk) amp. That could be easily fixed by replacing a single fuse. If there are similar fuses in these modern amps I would happily take the thing apart and see what I can sort.

    Thanks for any advise from those in the know :thumbsup:
     
  2. Bagger

    Bagger
    Active Member

    Joined:
    May 8, 2007
    Messages:
    2,225
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    66
    Location:
    Leicester
    Ratings:
    +227
    Might be worth trying a full system reset before pulling it a part.

    Usually requres you holding in 2 buttons on the front panel while turning on the mains.
    Check the manual see which ones they are
     
  3. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    Already tried that but thanks for the advise :thumbsup:
     
  4. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    Up we go to find the tech savvy repair people :thumbsup:
     
  5. JH4

    JH4
    Well-known Member

    Joined:
    May 6, 2003
    Messages:
    2,467
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    83
    Ratings:
    +299
    Denon amps have several fuses in them. It's a simple task to open the case and take a look. If the replacement fuse blows again, (with no speakers connected), then I would check the output transistors for that channel first, and take it from there.
    You could get readings from the good channel to compare, which should lead you in the right direction, if you can't get access to a service manual.
     
  6. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    Thanks JH4, sound advise to start with. Time to get the multimeter out :thumbsup:
     
  7. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    Well, not looking to difficult to diagnose. Amp has a crack on one of the circuit boards connected to the speaker outputs, great :rolleyes:

    Seller says everything was fine before sending, packaging is in perfect condition so don't stand much chance with the courier. At a total loss of near £200 (unless someone knows a cheap electronics repair place) I don't think I will buy heavy, expensive elecronics 2nd hand again unless I can test and collect :thumbsdow
     
  8. 12 promises

    12 promises
    Active Member

    Joined:
    Aug 18, 2004
    Messages:
    1,555
    Products Owned:
    2
    Products Wanted:
    1
    Trophy Points:
    66
    Location:
    dunfermline
    Ratings:
    +119
    Richer sounds do a standard charge for inspection then add repair to the cost but also give the gubbings a full overhaul.........worth a thought.
    or.............claim your household insurance?
    or get a refund from the seller.
     
  9. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    Regarding repair it is very plain to see what the fault is so I will get a price from the Denon repairs specialists for the part or I may take the board out and down to an electronics guy I know to see whether he can re-create the broken connections. There isn't much point taking it somewhere that will charge to open it up as there is a good chance the part will be more costly than the amp was.

    My first call for the cash will be to try the courier. Unfortunately I really can't see them accepting that an item with no visible damage to the packaing or casing is their responsibilty. I also don't think it would be fair to request a full refund or payment for repair from the seller who is adamant that the item was fine when sent. Although a little of the polystyrene packing was missing I would have thought that bad handling from the courier (DHL) is the more likely cause of the damage. Obviously it is perfectly possible that I was just sent someones broken amp, but the seller seems nice and genuine so I am sure it is just an unfortunate situation.

    In my humble opinion both buyer and seller were happy for the item to be couriered so I would hope for a midway meeting on costs. If he doesn't agree though I will have a broke amp and he has the agreed cash in full. That will be very depressing considering I never recieved the goods in working order.

    Sadly I have cheapo house insurance that does not cover the likes of accidental damages. Along with the fact that it is about to come up for renewal means that option will probably come straight back in a raised premium.
     
  10. Bagger

    Bagger
    Active Member

    Joined:
    May 8, 2007
    Messages:
    2,225
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    66
    Location:
    Leicester
    Ratings:
    +227
    Repair should be straight forward assuming its only double or single sided circuit board. ( multi layer is a whole different game )
    Should just be a matter of re joining the broken tracks on the PCB.
    A fine tipped soldering iron a steady hand and plenty of patience is all that is needed.

    And the ability to solder of course
     
  11. Mr Incredible

    Mr Incredible
    Distinguished Member

    Joined:
    Dec 2, 2003
    Messages:
    23,918
    Products Owned:
    2
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    The Fylde Coast
    Ratings:
    +13,617
    Even well packaged goods are not designed to withstand dropping from the height of a truck tailgate. "Normal" shipping should not damage the goods internally. A cracked board suggests the box was dropped. I'd contact the seller and the courier and see what can be done, particularly if the unit was packed with Denon's own packing materials.
     
  12. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    I am not too bad at point soldering and fault finding so it could be worth a shot. It looks like it should be a single layer, simple board, the complex electronics are all in the front panel. Would soldering standard wire in place of the broken tracks be sufficient? Also would it be worth drilling a definate seperation into the damaged area to make sure there is no possibility of contact / shorting. I find it amusing how much people spend on cable to their speakers when you see that internally it is being moved aroung in single core cable with less than 1mm gauge :suicide: .

    Having a bit of difficulty getting the board out though due to the wide variety of unique connections to dismantle. I removed all the smaller boards that side of the heat sink last night to fully expose the amplification board and the speaker termination board. Disconnecting the amplification board though is not looking so easy as it has a number of connections that look like hard wiring. Without removing that and the heatsink I can't get the damaged board out :mad:

    Put it all back together to check i hadn't made things worse and all was fine :thumbsup: . I might still ask the electronics guy I know for a quote to see if it would be worth letting him take the risk of making it worse.
     
  13. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    The internal packaging was Denon's own, but a couple of the polystyrene parts had clearly lost bits when originally upacked or when re-boxing. It was holding pretty well though so given the nature of the problem I think a drop is really the cause. I am not going to get anywhere with the courier though as the box and item are in apparent perfect condition so it is very difficult to prove. The fact that I can't seem to get the manifest of the sender before the cut off point for a claim is also not helping, as isn't a shortfall in the insurance level of around one half :suicide:
     
  14. Bagger

    Bagger
    Active Member

    Joined:
    May 8, 2007
    Messages:
    2,225
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    66
    Location:
    Leicester
    Ratings:
    +227

    If the circuit board is completely snapped then its worth gluing first with an epoxy resin glue. so everything is lined up nicely
    gently sand off the solder resist resin across all the broken tracks.
    Tin the tracks and lay some solid core wire across the break and solder in place. Use some thing like kynar wire, comes in various thickness`s right down to .5 mm

    good luck :)
     
  15. sibeer

    sibeer
    Well-known Member

    Joined:
    Jul 17, 2005
    Messages:
    2,844
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    West Kirby, Wirral
    Ratings:
    +129
    Thanks for the advise Bagger :thumbsup:

    I have some ultra fine Kynar that I used to mod my Xbox. Will that definately be fine for use with speaker level current? I don't mind ordering something a bit more substantial if it will be more suitable :thumbsup:
     
  16. Bagger

    Bagger
    Active Member

    Joined:
    May 8, 2007
    Messages:
    2,225
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    66
    Location:
    Leicester
    Ratings:
    +227
    That should be fine
    The wire is really to help the mechanical strength of the joint. You can just bridge the broken track with solder and it`ll work fine but isnt too strong.
    If the track is quite wide double, treble up if need be, But still bridging the broken area fully with solder.
     

Share This Page

Loading...