Bush Arena BH4000
 

Hi - can anyone here help me to find a schematic for a Bush Arena BH4000? I bought mine as a teenager in the 70s and now I'd like to restore it. I believe (looking at google photos) that perhaps it was also marketed as the Rank Arena T4000. I'm sure I saw - a few years ago - someone advertising the schematic for $20 but can't seem to find it now.

Re: Bush Arena BH4000
 

Hi and welcome to the forum.

The BH4000 was mentioned in this old thread and samjmann stated he had a copy of the manual, maybe drop him a PM.

https://www.vintage-radio.net/forum/...d.php?t=136287

The Rank T4000 is shown here (with circuits)

https://www.radiomuseum.org/r/rankar...000_t4000.html

Cheers

Mike T

Re: Bush Arena BH4000
 

Thanks Mike. The second link leads to a page where you can request the schematic, but it sends only a truncated version - and the opportunity to pay $25 to get full access - maybe that's what I'd seen before? I'll wait to see if samjmann has anything first! Cheers.

Re: Bush Arena BH4000
 

The radio museum site schematic has three pages, you can download all three in one day. I understand the $25 dollars is to join the site and have unlimited downloads but they only have those 3 pages for this model.
That’s how I understand it.

Re: Bush Arena BH4000
 

Thanks Frank - got it! You're right, you have to scroll the thumbnails and request a download for each part - I can print these out and stick them together. Just hope the Rank T4000 is identical to the Bush BH4000 - the pictures certainly look the same.

Re: Bush Arena BH4000
 

Hi I have the full bush arena t4000 4500 service manual if you need any part let me know. Jim

Re: Bush Arena BH4000
 

Hi cambush.

Like you, I bought my BH-4000 as a teenager back in 1975. It had B&O styling but at a cheaper price!

Have a look in your PM's my message is there. As regards the B-4000 access to the amp is quite difficult and you have to remove various spring clips to get access to the innards. It's a good idea to have as much info as well as the schematic. I think the circuit for the T-4000 is different to that of the BH-4000. The T-4000 and the RTA-2000 all suffered with electrolytic cap failure in the signal path, not just the PSU etc. This was happening back in the seventies! What they're like now is anyones guess!

SJM.

Re: Bush Arena BH4000
 

Hi Big_jim, samjmann is hopefully getting a schematic for me, but if you have a full service manual that would be fantastic!

Re: Bush Arena BH4000
 

Hi which part or parts of the manual do you need! It has 45 pages
Cheers. Jim

Re: Bush Arena BH4000
 

Hi Big_jim - is it a user manual or a service manual (with things like test voltages etc?) - I'd be interested in the latter if it talks about the power output stage or the tone control.

Re: Bush Arena BH4000
 

part 1

Re: Bush Arena BH4000
 

part 2

Re: Bush Arena BH4000
 

part 3 if you need anymore let know.

if i was you i would have a bag of 10uf 50v caps and replace ever one you see

jim

Re: Bush Arena BH4000
 

Wow - Jim, that's tremendous! Let me see how far I can get and I'll let you know if I need any other pages. Great tip about the caps too... I remember taking it apart in my teens for something and getting in a terrible tangle with the pulleys and string for the tuner indicator. Let's see if an extra 45 years' experience counts for anything!

Re: Bush Arena BH4000
 

Quick update - I dismantled my BH4000 (no easy task) and it's a bit of a horror show. At some point in the distant past it looks like I replaced the power output stage with a couple of integrated power amps (one marked RS 303-236, the other ILP HY60 but otherwise identical). I can only imagine that there was originally some circuit board with the power transistors bolted to the back of the chassis as a heat sink, but no sign of them. What was I thinking? Can anyone confirm if indeed such a circuit board should be there (in the big gap in the photo)? ******************************mgtWoZ7h9vmHP3PR8

Also, any tips on how to remove the filter circuit board - the one with the sliders? Seems immovable...

Re: Bush Arena BH4000
 

Yes there should be 2 power amp pcb's I've also noticed I haven't uploaded them pictures and circuits! If I have time I will in the morning or definitely the weekend. Jim

Re: Bush Arena BH4000
 

I'm gutted - can't believe I would have been so stupid to have just thrown away the old ones - think I'll have to go routing through all my old boxes in the garage! I suppose as a last resort I could fabricate replacement PCBs using your service manual photos as a starting point.

Re: Bush Arena BH4000
 

T4000

Re: Bush Arena BH4000
 

t4000

Re: Bush Arena BH4000
 

Apologies cambush for not sending the scans. Big Jim came to the rescue I see! Been stupidly this week, slipped my mind.
Such a shame the amp pcb's are missing. Hope your garage search is successful. SJM.