lolo-m
Well-known member
I'm sure you do need a second transfo if you regulate the 6,3V. The rondo isn't powerfull enough to drive the slow Start PSU in a stereo comp.radiance said:
the Poor Man 660 support thread
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[silent:arts]
Well-known member
lolo-m said:
since the rondo was there before the slow start PSU ...
set the heaters to anything near 6V is fine.
however, the 9V heater winding won't affect the high voltage PSU or any blowing IRF840.
lolo-m
Well-known member
I don't say anything else... I don't blame anybody... It's a fact.[silent:arts] said:
And if I forgot to say this before:
Tanks to silent:arts and analag for this project :-* !
hello!
in fact my 6.3 volt are ok with slow start pcb one channel draw about 2,4 A so two would be about 4,8 5 A
i am in the range of rondo transf.(9v-6A)
the problem in in the high voltage section! i can not use two channel together
because the voltage drop down after 1min or less to 200....and if i wait more ..drop to 40 irf (q4)dead
if i use just 3 tube per channel same probl.
i can put just one tube on the second channel 6bc8
have some IRFB11N50A are little more powerful think!
what do you think volker?
in fact my 6.3 volt are ok with slow start pcb one channel draw about 2,4 A so two would be about 4,8 5 A
i am in the range of rondo transf.(9v-6A)
the problem in in the high voltage section! i can not use two channel together
because the voltage drop down after 1min or less to 200....and if i wait more ..drop to 40 irf (q4)dead
if i use just 3 tube per channel same probl.
i can put just one tube on the second channel 6bc8
have some IRFB11N50A are little more powerful think!
what do you think volker?
kazper
Well-known member
dingo said:
I think you need to read my post a page or two back, where I recap some of Analag's PSU recommendations.
The voltages I measured where with a Edcor power transformer so if your voltages are higher you may need to salt to taste.
Regarding the chip, in the 13X pages of this thread there is talk of one of the types of that chip to "work better" than others. Read up and do those fixes, and make sure your chip is the correct version.
PS, my PSU are working fine as the schematic, but I'm about to mod one set as Analag recommended. Once this is done I'll post a new voltage chart and note any differences.
mitsos
Well-known member
- Joined
- May 4, 2007
- Messages
- 2,886
hey guys, to add one more.. I finally got mine to "work" without the excessive hum and buzz I had before. Mine is still naked, so there will be some improvements once it's in a case.. I have a one channel build, PSU is "corrected," per analag's comments, with a 0.33uF film cap (what I had around) instead of the 47uF on the schematic/BOM. All else is stock, but it wasn't working, so I added 4x6800 uF to the heater supply, 13600 before the big resistor and 13600 after. Made a large difference in hum, and my meter finally worked (it lives pegged to the right until compression occurs, then shows compression, but after I stuck the caps in it went to 0VU). Anyway, I still had noise and hum which sort of oscillated, so I then removed one 5687.. After that and swapping the large resistor to get the voltage closer to 6.3, it worked fairly well (but my meter went pegged again).. There is still some hum (didn't check SNR so I can't tell you how far down, but I can't hear it under normal conditions, just if I have my phones or monitors at full volume. Anyway, it sounds nice so far, I'll probably mod the time constants eventually, but I am glad I kept this thing. Maybe I'll do a second channel P2P.
anyway, to those of you who had this problem where removing one 5687 made the thing work, how did you handle it finally? Radiance I saw your build has 4 tubes per channel, so you must have used other tubes than the originals you had (IIRC you had this problem initially)?? KHStudio, you still have this issue?
Is this just a matter of mis-matched tubes?
thanks!
anyway, to those of you who had this problem where removing one 5687 made the thing work, how did you handle it finally? Radiance I saw your build has 4 tubes per channel, so you must have used other tubes than the originals you had (IIRC you had this problem initially)?? KHStudio, you still have this issue?
Is this just a matter of mis-matched tubes?
thanks!
radiance
Well-known member
All my weird problems were due to underpowered heater supply. For both normal and slow start heater PSU's the toroid is underpowered.
To get the required 4,8A you'll need a 7,87A toroid.
Have a look at the pic attached.
To get the required 4,8A you'll need a 7,87A toroid.
Have a look at the pic attached.
hello!
have just measured the rondo trnsf. the high rail measure about 47-48 ohm
all other rail measure less about 00.6
are those value right?
can use just one channel with all tubes if use two channel the high rail fail!!
all the other voltage are there !
have just measured the rondo trnsf. the high rail measure about 47-48 ohm
all other rail measure less about 00.6
are those value right?
can use just one channel with all tubes if use two channel the high rail fail!!
all the other voltage are there !
skal1
Well-known member
ok need help with this, will this power my heater ....
http://cgi.ebay.co.uk/Transformer-EMT-477-PCB-0-120-0-120-0-15-0-15-12VA-/160356433467?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item2555fcfe3b
cheer
http://cgi.ebay.co.uk/Transformer-EMT-477-PCB-0-120-0-120-0-15-0-15-12VA-/160356433467?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item2555fcfe3b
cheer
radiance
Well-known member
skal1 said:
No, see post below...
(before I said: In theory yes, but you'll have to bring down the voltage from 15V to 6,3V which will generate too much heat at the required current....) disregard...
I think you need a lot more power than these Skal1. if you need 7.87A (like Radiance said) and take 9VAC secondaries that is 71VA more or less. Two 9VAC secondaries with 4A each one would be 72VA (and you use them in paralel). The one you say is only 12VA... I think something like 0,8A each 15Vac secondary, and 15Vac maybe is too much. It seems to me a lot of power but I think that I do the maths well...
Arnau
Arnau
radiance
Well-known member
dingo said:
I suggest you re-read all your post and see what has changed after you dit some modifications to your PSU.
Maybe you see a pattern emerge...like you've come from a situation were you could power both channels ok, but after shutdown Q4 did not work any more. Now, you can only power 1 channel...things have changed it seems.
Somehow I think it has to do with the underpowered heater supply...I have no logical explanation for this but it might be an idea to get the heater supply fixed first.
In the long run you won't be able to power two slow start heater board with the toroid you have now.
Read my earlier post about this + attached pdf file.
radiance
Well-known member
dingo said:
Ouch...I thought that transformer was 12A :
mitsos
Well-known member
- Joined
- May 4, 2007
- Messages
- 2,886
Yes I understand that. IIRC when I got the trafo wound I spec'd 4A on the heater. The winder is trustworthy, but that doesn't rule out a mistake in his winding calculations. It does create some hum though... so I'm thinking of sticking it on the outside of the case, bolted to the back, old school style.radiance said:
Anyway, you added a beafier heater trafo and your PM works with the original 5687 tubes? I'll try to find another 6.3V trafo to try.
Mine seems to work fine with the single 5687 but I wonder if having only one tube means less power in the sidechain which means slower attack? But my meter is working after re-adjusting RV3 nd RV6.
thanks!
skal1
Well-known member
radiance said:
@radiance
ok you've lost me , will it work ? if not could you point me in to one that will power a stereo unit
cheer
skal1
that from Antek would work http://www.antekinc.com/details.php?p=36 . these are 100VA and have 5.6A per secondary, two 9V secondaries 11.2A in series... a lot much from 7.87A but antek jump from 50VA to 100VA, a 75VA with 9V secondaries would be ok if you want 7.87A... 75VA/9V=8.33A 100VA/9V=11,11A
radiance
Well-known member
skal1 said:
;D ;D ...I thought the toroid in your link was 12A ..but it was 12VA.
15V @ 12A should work in theory but bringing 15V down to 6,3V with these currents will generate too much heat....
15V @ 12VA will not work...that's 1,25A . You'll need at least 8A for the two heaters
skal1
Well-known member
radiance said:
thanks for clarification
skal1
skal1
Well-known member
ok me again will these work
http://uk.farnell.com/block/rk100-9/transformer-100va-2-x-9v/dp/1419553
http://uk.farnell.com/pro-power/ctfcs200-9/transformer-200va-2-x-9v/dp/1780903
cheers
skal1
http://uk.farnell.com/block/rk100-9/transformer-100va-2-x-9v/dp/1419553
http://uk.farnell.com/pro-power/ctfcs200-9/transformer-200va-2-x-9v/dp/1780903
cheers
skal1
radiance
Well-known member
skal1 said:
Yes & yes...what you need for 1 channel heater suply is a 9V 50VA or up transformer. These are 100VA and 200VA so they could power two channels.
