hi all, i am building this 2a3 pp kit as per here, 2A3 PP Push-Pull Tube Amplifier 15W Complete Kit (Stereo)_Power Amplifier Kit_Tube Amplifier Kit_Analog Metric - DIY Audio Kit
i dont know how to wire the output transformers up and my repeated emails to the company that sells them is getting nowhere. this is the output transformer. OP5K60ABPRO 60W 5K:4-8 Ohms Push-Pull Transformer Upright_Push Pull_Output Transformer_Analog Metric - DIY Audio Kit and wiring diagram is as follows. http://analogmetric.com/download/2A3 PP Amplifier Schematic.pdf
is there an easy way for me to work out which wire is which with a meter? It has a red/black/blue wire on one side and red/yellow/purple and a green/yellow earth wire the other side. many thanks in advance guys. ad
i dont know how to wire the output transformers up and my repeated emails to the company that sells them is getting nowhere. this is the output transformer. OP5K60ABPRO 60W 5K:4-8 Ohms Push-Pull Transformer Upright_Push Pull_Output Transformer_Analog Metric - DIY Audio Kit and wiring diagram is as follows. http://analogmetric.com/download/2A3 PP Amplifier Schematic.pdf
is there an easy way for me to work out which wire is which with a meter? It has a red/black/blue wire on one side and red/yellow/purple and a green/yellow earth wire the other side. many thanks in advance guys. ad
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As always - you get what you pay for.
If you bought on e-bay you could return it and buy from a reputable dealer.
Besides that, sorting the connectors should be straightforward. I assume
you have tree thicker wires and three thinner wires from the transformer.
The thicker is secondary ( to the speaker) the other to B+ and anodes.
If in doubt use an ohmmeter, there should be a significant differens in
resistans where the secondary has a few ohms and the primary tens of ohms.
When identifying the sides, use the same ohmmeter and measure between all 3 on the primary. The two with the highest resistance is the anode connections, and the remaning should be B+
The secondary might be trickier if the ohmmeter is less then good. Well
there is a trick.
Connect two of the primaries ( does not matter which) to a AC transformer that delivers 6-18V, then measure AC on the secondaries and make a note
the AC voltage between each combination. The pair with the highest voltage is the "outer side" and the remaining is the middle.
One thing remains, and that is the phase of the outlet. Leave that
for the moment, build the amp less the feedback resistor. Power up
with speakers or power resistor as load. If it starts oscillating when connecting the feedback , then the secondary has to be reversed.
Good luck ( and buy domestic next time)
You can find with multimeter in mode R 3 wires with about 200 and 2x 100 ohms. Middle is for +U from PSU.
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For secondary.....you can find 3 wires with about 0.8 ohms /0.5 + 0.3/. 0.8 is for 8 ohms, 0.5 for 4 ohms appr.......
Are you sure this seller, Analog Metric is reliable as I bought a few items from them but I didn't received them.
hi all and thanks for the responses. i will read each one over a few times to digest the info and hopefully get to grips with it. analog metric sell some great gear and superb prices but of late they seem to be going down hill. i ordered my 2a3pp amp about 2 years ago and its been this long in building so he is not as commited to answering my questions as a seller would be if it was a few weeks ago. the last pre amp kit i got from him was full of crap quality parts and half the valves missing!! i had luckily still got my 45 days of paypal cover so he sent me replacement quality parts and the missing bits. why on earth he expected to me to accept the rubish bits i cant quite fathom and some days questions get a next day response and some get no response at all!! the level of service goes from superb to non existent. its actually such different behaviour i would call it strange! i dont need any more parts or going to be doing any more building but needless to say if i was it would not be purchased from analogmetric. if you was to use them then worth paying the slightly higher prices through ebay but as with all chinese purchases you can be nearly out of paypal protection when the item arrives and in the case of faulty gear it can cost a fortune to return it which you are not likely to be reimbursed for. after that whinge i must say most stuff from china which prices seem to be verging on impossible i have been 95% of the time very happy with.
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