Output Transformers OP1- OP58 For sale.

transformers-massed-for-sale-10-dec-08.jpg

58 different types of output transformers are for sale.

This page lists OP1 to OP16. SE and PP, with full information.


For OP17 to OP58, Go to
OP17 to OP58 SE and PP, short description only.

Conditions of sale, other information about OPTs, PLEASE READ :-

Output Transformer Notes, December 2008.


Orders are by email to Patrick Turner, info@turneraudio.com.au

If ordering, describe your project, tube types, loudspeaker sensitivity

and nominal impedance.

Freight to countries outside Australia will be high and not included in prices.

If you wish to know freight costs, try adding 20% to weight of transformer

listed and get estimates for cost using an online freight calculator by freight companies.
My postcode is Australia 2602

Payments are by direct deposit to my bank account, postal money order,

bank cheque, or by cash if transformers are collected at my premises.
I do not have credit card, PayPal facilities.

A compatible set of iron wound parts including a power transformer,

output transformer and choke for B+ filtering to an amplifier can be
supplied to best suit your project.

WARNING : Users of these transformers must install
earthed metal enclosures over transformers screw fixed
to chassis to prevent any contact with high voltages.

See examples of suitable enclosures at 5050amp,  or  8585 amp.

See example of potted transformer with C-cores.

Before sale, most transformers require some additional work including varnishing,
painting, labeling and provision of mounting brackets for top-of-chassis mounting.
 

EXAMPLE...
Here are pictures of the last set of output transformers. OP22, sold February 2011
with a pair of 1.9H chokes...

2xop22+2x2hchokes-bench2-feb2011.jpg
The picture shows the pair of OP22 on the left plus a pair of filter chokes on the
right sold in Feb 2011 to a customer who is building a stereo amp with 4 x EL34
in each channel.
There are multiple leads to the OPT for :-
Secondary speaker winding,
Primary anode winding with 75% of primary turns,
Primary cathode feedback winding with 25% of primary turns,
There are 25% taps off the anode windings to allow for bootstrapping of anode
load resistors of driver stage.
These OPT have been configured for 25% CFB with a fixed screen voltage supply,
but could easily be changed to suit UL, Triode or Pentode connection without CFB.

Leads provided are 300mm long. Support brackets may vary in future from what
is shown using 3mm thick aluminium plates and 5mm threaded rod bolts.
The OPT have labels indicating connections.

OP1,
Weight 7.4Kg, o/a size 176mm x 132mm x 138mm.
560:1or4,  843:1.5or6,  1k1:2or8,  1k7:3or12,  2k2:4or16,  2k8:5or20, 
3k3:6or24,  4k4:8or32. 
PP, Ea = +600V, Eg2 = +400V, 8 x 6550/KT88, 300W+ PP AB1,
beam power mode, 2k2 : 4.     
For Hi-Fi use UL or CFB, Ea = +500V and 6 x 6550/KT88 for 100W+ AB1,
2.8k:5 ohms; proportion of class A1 power = 30W. Multiple EL34, triode possible.
SE CFB, SEUL, +air gap, 40W into 840:6 ohms, 4 x 6550, 6 x EL34,
Ea = +300V, Ia = 320mA.
SE Triode, +air gap, 40W into 840:6 ohms, 6 x 6550, 6 x EL34,
Ea = +420V, Ia = 325mAdc.
Primary = 1,496t of 0.45dia, 11 layers 136t. 
Secondary = 12 layers 63t of 1.0dia, Ns = 63 or 126.
PP Interleaving = 11P x 12S,  Ips = 0.22 Nomex. Core = 52/52/76/28.
Price, 1 pair available, aud $800.00 for the pair.
OP1-4-12-08
OP2,
Weight 7.6 Kg,  oa size195mm x 130mm x 153mm.

1k4:4or1,  1k75:5or1.3,  2k1:6or1.5,   2k8:8or2,  3k5:10 or 2.5, 4k2:12or3,   5k6:16or4.
PP, Ea = +600V, Eg2 = +400V, 8 x 6550/KT88, 300W+ PP AB1, beam power mode, 2k1:6ohms.
For Hi-Fi use UL or CFB use Ea = +400V and 6 x 6550/KT88/KT90 or 8 x EL34/6CA7 for 100W+ AB1, 1k2:4 ohms; proportion of class A1 power = 24W.
SE, Hi-Fi, CFB, SEUL, +air gap, 54W into 1k3:6 ohms, 6 x EL34. Ea = +415V, Ia = 320mAdc.
SE Triode mode, 44W, 6 x 6550, Ea = +485V, Ia = 300mAdc.
Primary = 868 turns of 0.45dia plus 2 x 181 turns of 0.3dia  each side of the 868t for a total of 1,230t for PP. For SE, Np is configured with 181t in parallel for 1,049t to allow Idc up to 325mAdc.
For PP calcs, use Np = 1,230t, 0.3mm dia, 200mAdc max each side. Ns =  35 or 70, 8 x 35tpl, 1.8mm dia. Core = 56/50/76/28, PP Interleaving = 9P x 8S,  Ips = 0.22 Nomex.
Price, 1 pair available, aud $800.00 for the pair.
OP2-4-12-08.jpg
OP3,  SOLD
Weight 5.6Kg, o/a size 150mm x 140mm x 133mm.
870:1or4, 1k3:1.5or6,  1k7:2or8,  2k6:3or12, 3k5:4or16, 5k2:6or24.
PP, Ea = +600V, Eg2 = +400V, 8 or more 6550/KT88, 250W+ PP AB1, beam tetrode, 1k7:2or8.
Hi-Fi use, UL or CFB, Ea = +500V and 6 x 6550/KT88/KT90 for 118W AB1, 3k5:4 ohms; proportion of class A1 power = 33W. Lower power PP triode OK.
SE, CFB, SEUL, +air gap, 44W into 1k3:6ohms, 4 x 6550. Ea = +365V, Ia = 300mAdc.
SE Triode mode 4 x 6550, 31W into1k3:6, Ea 415V, Ia 240mA.
SE, CFB, SEUL, 60W into 1k3:6, 6 x 6550, Ea = +445V, Ia = 325mAdc.
Triode mode, 44W, 6 x 6550, Ea +500V, Ia 300mA.
Primary = 2,360t of 0.6dia, 20 layers 118t.  Secondary = 10 layers 80t of 1.0dia, Ns = 80 or 160.
PP Interleaving = 10P x 10S,  Ips = 0.22 Nomex. Core = 38/50/88/33.
Price, 1 pair available, aud $600.00 for the pair.
OP3-4-12-08.jpg
OP4,
Weight 5.5Kg, o/a size 152mm x 105mm x 130mm.
1k9:3or12,   2k5:4or16,   3k2:5or20,  3k8:6or24,  5k0:8or32.
PP, Ea = +500V, Eg2 = +400V, 4 or more 6550, 100W+ PP AB1, beam power mode, 2k5:4.
For Hi-Fi use UL or CFB, Ea = +450V and 4 x 6550 for 90W AB1, 2k5:4 ohms; proportion of class A1 power = 20W+. Multiple EL34, 6L6 possible as well as triode operation.
SEUL, CFB, tetrode, +air gap, 32W into 3k0:4.7 ohms, 3 x 6550, Ea = +485V, Ia = 150mAdc,
SE Triode, 25W 2k5:4, 4 x EL34, Ea = +485V, Ia = 150mAdc.
Primary = 1,661t of 0.3dia, 11 layers 151t.  Secondary = 10 layers 66t of 0.75dia, Ns = 66 or 132.
PP Interleaving = 11P x 10S,  Ips = 0.22 Nomex. Core = 48/50/62/25.
Price, 1 pair available, aud $600 for the pair.
OP4-4-12-08
OP5, 
Weight 5.5Kg, o/a size 152mm x 140mm x 133mm.
2k1:4or16,   2k6:5or20,    3k2:6or24,  4k2:8or32.
PP, Ea = +500V, Eg2 = 400V, 4 or more 6550, 90W+ PP AB1, beam tetrode mode, 2k1:4
For Hi-Fi use UL or CFB, Ea = +450V and 4 x 6550/KT88/KT90 for 90W AB1, 2k6:5 ohms; proportion of class A1 power = 20W+. Multiple EL34, 6L6 possible as well as triode operation.
SE, CFB, SEUL, beam tetrode, +air gap, 30W, 3k2:6 ohms, 3 x 6550, Ea = +500V,
Ia = 150mAdc.
SE Triode,  22W 3k2:6,  3 x 6550, Ea + +500V, Ia = 150mAdc.
Primary = 1,520t of 0.3dia, 10 layers 152t.  Secondary = 11 layers 66t of 0.75dia, Ns = 66 or 132.
PP Interleaving = 10P x 11S,  Ips = 0.22 Nomex. Core = 48/50/62/23.
Price, 2 pairs available, aud $600.00 for 1 pair.
OP5-4-12-08
OP6,
Weight 5.2Kg, o/a size 140mm x 94mm x 118mm.
1k0:3or12,  1k3:4or16,  1k6:5or20,  2k6:8or32.
PP, Ea = +430V, Eg2 = 400V, 4 or more 6550/KT88, 6 x EL34, 80W+ PP AB1, UL mode, 2k6:8.
For Hi-Fi, UL or CFB, Ea = +400V, 4 x 6550/EL34 for 70W AB1, 2k6:8 ohms; proportion of class A1 power = 30W+. PP Trioded 6550/EL34 possible, less power.
SE, CFB, SEUL, +air gap,  46W, 2k2:7, 4 x 6550, Ea = +500V, Ia = 200mAdc.
SE Triode, 33W, 1k9:6, 4 x 6550, Ea = +500V, Ia = 200mAdc.
Primary = 1,540 of 0.35dia, 11 layers 140t.  Secondary = 12 layers 80t of 0.55dia, Ns = 86 or 172.
PP Interleaving = 11P x 12S,  Ips = 0.22 Nomex. Core = 44/38/62/22.
Price, 1 pair available, aud $550 for the pair.
OP6-4-12-08
OP7,
Weight 3.2Kg, o/a size 100mm x 108mm x 105mm.
864:1or4, 1k3:1.5or6,  1k7:2or8,  2k6:3or12, 3k5:4or16, 5k2:6or24, 6k8:8or32.                            
PP, UL, CFB, beam tetrode, Ea = Eg2 = 400V, 2 x 6550, 48W AB1, 4k0:4.7 ohms.
SE, CFB, SEUL, +air gap, 18W, 1k7:8, 2 x 6550, Ea = +300V, Ia = 150mAdc.
SE Triode, 15W, 1k4:6.6 ohms, 3 x EL34, Ea = +400V, Ia = 150mA.
Primary = 1,694t of 0.35dia, 14 layers 121t.  Secondary = 8 layers 59 of 0.85dia, Ns = 59 or 118.  
PP Interleaving = 7P x 8S,  Ips = 0.22 Nomex. Core = 25/50/62/22.
Price, 1 pair available, aud $400.00 for the pair.

OP7-4-12-08
OP8,  SOLD
Weight 4.3g, o/a size 150mm x 100mm x 105mm.
1k5:6or1.5,   2k:8or2,    3k:12or3,   4k:16or4,   5k1:20or5,   6k1:24or6,  8k2:32or8.
PP, UL, CFB, beam tetrode, 4 x 6550, Ea = +450V, Eg2 = 400V, 80W+ PP AB1, 4k:4.
50W with PP triodes.
SEUL, CFB, +air gap, 35W, 1k5:6, 4 x EL34, Ea = +350V, Ia = 260mAdc.
SE Triode,  25W, 1k5:6, 4 x 6550, Ea = +500V, Ia = 220mA.
Primary = 1,920t, 0.45dia, 16 layers 120t, Secondary = 8 layers of 60t, 0.9dia, Ns can be 60 or 120.
PP Interleaving = 9P x 8S,  Ips = 0.22 Nomex. Core = 46/38/65/25.
Price, 1 pair available, aud $480.00 for the pair.
OP8-4-12-08
OP9,
Weight 2.6Kg, o/a size 102mm x 95mm x 95mm.
1k3:2or8,   1k9:3or12,   2k5:4or16, 3k2:5or20, 3k8:6, 5k0:8or32.
PP, UL, CFB, beam tetrode, Ea = Eg2 = 400V, 2 x EL34, 30W AB1, 5k0:8 ohms.  With Ea =          +350V, get 22W pure class A1, 5k0:8.
SE, CFB, SEUL, +air gap, 18W, 4k5:7 ohms, 2 x EL34, Ea = +450V, Ia = 100mAdc.
SE, CFB, SEUL, +air gap, 18W, 1k3:8 ohms, 2 x EL34, Ea = +275V, Ia = 175mAdc.
SE Triode, 14W, 3k2:5 ohms, 3 x EL34, Ea = +450V, Ia = 100mA.
Primary = 2,160t, 0.35dia, 18 layers 120t.  Secondary = 9 layers 86t, 0.55dia, Ns = 86 or 172.
PP Interleaving = 10P x 9S,  Ips = 0.22 Nomex. Core = 25/38/62/22.
Price, 1 pair available, aud $400 for the pair.
OP9-4-12-08
OP10,
Weight 2.6Kg, o/a size 102mm x 95mm x 95mm.
2k0:1or4,  3k0:1.5or6,  4k0:2or8,  6k0: 3or12, 8k0:4or16, 12k0:6or24, 16k0:8or32.
PP, UL, CFB, beam tetrode, Ea = Eg2 = 400V, 2 x EL34, 30W AB1, 4k0:8 ohms. With 12k0:6,   get 22W pure class A1.
SE, CFB, SEUL, +air gap, 17W, 4k0:8 ohms, 2 x EL34, Ea = +450V, Ia = 110mAdc.
SE, CFB, SEUL, +air gap, 18W, 3k0:6 ohms, 2 x EL34, Ea = +360V, Ia = 120mAdc.
SE Triode, 12W, 2k3:4.7 ohms, 2 x EL34, Ea = +400V, Ia = 110mA.
Primary = 2,688t, 0.28dia, 16 layers 168t.  Secondary = 8 layers 59t, 0.85dia, Ns = 59 or 86 or118.
PP Interleaving = 9P x 8S,  Ips = 0.22 Nomex. Core = 25/38/62/22.
Price, 1 pair available, aud $400.00 for the pair.
OP10-4-12-08
OP11, 
Weight 3.2Kg, o/a size 102mm x 95mm x 95mm.
1k2:4,  1k5:5,   1k8:6, 2k4:8,   PP, UL, CFB, beam tetrode, Ea = Eg2 = +400V, 4 x EL34, 60W AB1, 2k4:8 ohms. With Ea = +300V, 45W, 4 x EL34, 2k4:8, more class A with higher Ia.
SE, CFB, SEUL, +air gap, 25W, 1k5:5, 3 x EL34, Ea = +350V, Ia = 200mAdc.  SE Triode, 17W, 1k5:5 ohms, 3 x EL34, Ea = +400V, Ia = 160mA.
Primary = 1,696t, 0.4dia, 16 layers 106t.  Secondary = 9 layers 98t, 0.45dia, Ns = 98.
PP Interleaving = 10P x 9S,  Ips = 0.22 Nomex. Core = 26/50/62/22.
Price, 1 pair available, aud $400.00 for the pair.
OP11-4-12-08
OP12, 
Weight 4.0Kg, o/a size 115mm x 90mm x 98mm. E&I laminated  core, GOSS.
2k0:2or8,   3k0:3or12,  4k0:4or16,  5ko:5or20,  6k0:6or24, 8ko:8or32.   PP, UL, CFB, beam tetrode, Ea = Eg2 = +400V, 2  x  EL34, 40W AB1, 6k0:6 ohms. With Ea = +300V, 25W, 2 x EL34, 6k0:6, more class A with higher Ia. SE cannot be done with this transformer because the E&I laminations cannot easily be air gapped.
Primary = 2,592t, 0.28dia, 16 layers 162t.  Secondary = 8 layers 81t, 0.5dia, Ns = 81 or 162.
PP Interleaving = 9P x 8S,  Ips = 0.22 Nomex. Core = 38/40/57/19.
Price, 1 pair available, aud $300.00 for the pair.
OP12-4-12-08
OP13,                                                  
Weight 2.6Kg, o/a size 100mm x 75mm x 82mm. E&I laminated  GOSS core. 1k9:8  , k9:2or8,   2k9:3or12,  3k9:4or16,  4k9:5or20,  5k9:6or24, 7k9:8or32.                                 
PP, UL, CFB, beam tetrode, Ea = Eg2 = +350V, 2  x  EL34, 25W AB1, 5k9:6, SE cannot be done with this transformer because the E&I laminations cannot easily be air gapped.
Primary = 2,000t, 0.28dia, 16 layers 125t.  Secondary = 4 layers 63t,0.6dia, Ns = 63 or 126.
PP Interleaving = 5P x 4S,  Ips = 0.22 Nomex. Core = 32/40/48/12.
Price, 1 pair available, aud $180 for the pair.
OP13-4-12-08
OP14, 
Weight 3.2Kg, o/a size 102mm x 95mm x 95mm.
1k2:4,  1k5:5,   1k8:6, 2k4:8,   PP, UL, CFB, beam tetrode, Ea = Eg2 = +400V, 4 x EL34, 60W AB1, 2k4:8 ohms. With Ea = +300V, 45W, 4 x EL34, 2k4:8, more class A with higher Ia.
SE, CFB, SEUL, +air gap, 25W, 1k5:5, 3 x EL34, Ea = +350V, Ia = 200mAdc.  SE Triode, 17W, 1k5:5 ohms, 3 x EL34, Ea = +400V, Ia = 160mA.
Primary = 1,696t, 0.4dia, 16 layers 106t.  Secondary = 9 layers 98t, 0.45dia, Ns = 98.
PP Interleaving = 10P x 9S,  Ips = 0.22 Nomex. Core = 26/50/62/22.
Price, 1 pair available, aud $400.00 for the pair.
OP14-4-12-08
OP15,
Weight 3.2Kg, o/a size 102mm x 95mm x 95mm. Only SE possible.                                                  
1k3:2or8,  1k9:3or12,  2k6:4or16, 3k2:5,  3k8:6or24, 5k1:8or32.   SEUL, SECFB, +air gap, 25W   3k2:5, 3 x EL34, 2 x 6550, Ea = 410V, Ia = 140mAdc.
SE Triode, 16W, 3k2:5 ohms, 3 x EL34, 2 x 6550, Ea = +460V, Ia = 125mA.
Primary = 2,440t, 0.35dia, 20 layers 122t.  Secondary = 10 layers 96t, 0.5dia, Ns = 96 or 192.
PP Interleaving = 11P x 10S,  Ips = 0.22 Nomex. Core = 26/50/62/22.
Price, 1 pair available, aud $400.00 for the pair.
OP15-4-12-08
OP16,
Weight 3.8Kg, o/a size 115mm x 105mm x 102mm. Only SE possible.          1k5:2or8,  2k3:3or12,  3k0:4or16, 3k8:5,  4k6:6or24, 6k1:8or32.  
SEUL, SECFB, +air gap, 19W   3k8:5, 2 x 6550, Ea = 420V, Ia = 120mAdc.
SE Triode, 15W, 3k8:5 ohms, 3 x EL34, 2 x 6550, Ea = +480V, Ia = 110mAdc.
Primary = 1,830t, 0.35dia, 15 layers 122t.  Secondary = 8 layers 66t, 0.75dia, Ns = 66 or 132.
PP Interleaving = 9P x 8S,  Ips = 0.22 Nomex. Core = 32/50/62/22.
Price, 1 pair available, aud $450.00 for the pair.
OP16-4-12-08


30Watt OPT with C-cores.
Potted in octagonal steel enclosure with polyester casting resin.
The pot was well painted before bolting to a chassis for a stereo amp with
2 x EL34.

OPT18-potted-5-jan09.jpg

OPT18-potted-4-jan09.jpg

OPT18-potted-2-jan09.jpg


Go to OP17 to OP58

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