Bugle 45

Thanks. See the pics, one from each mono. They are very hard to see, and my soldering skills leave much to be desired. It may be better to look at the sketch a few posts back.

Also, perhaps the steps below may help:
1) Tie 1 and 7 together.
2) One of the two heater wires goes to both 4 and 5. The other heater wire goes to 9.
3) 1 Kohm resistor between 1 and 8.
4) The 0.047uF resistor goes to 8. The other end goes to the grid of the 45 tube socket.
5) 1 Kohm resistor goes to 2. The other end goes to Input+.
6) The 27.4Kohms and 10uF SCR go to 6 then to ground.


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With vintage metal parts such as tube socket terminals or PIO capacitor terminals, I use a small file to gently polish the metal terminal before soldering. This makes the solder flow more easily.
 
Thanks, your written description was very helpful especially #2. It looks like the heaters are connected in parallel.
Would it be Ok to share one filiment transformer for both SRPP channels if built as a one chassis stereo amp?
 
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Thanks, your written description was very helpful especially #2. It looks like the heaters are connected in parallel.
Would it be Ok to share one filiment transformer for both SRPP channels if built as a one chassis stereo amp?
I think so according to the schematic. However, I am not an electrical person. Others may want to chime in.
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A quick update. Both amps have been in the sick bay. I bought four "Magnequest" transformers from Heyboer. One of them "died" fairly quickly - got replaced. Then, two more died in a few weeks. All three would blow the 3A fuses immediately on power up. Sent all four back to Heyboer. Arlyn and the gang looked at them. Determined that the "shield" was possibly oversized and likely caused the shorts in the three transformers. Totally rebuilt and shipped them back at no charge.

Lucky me, the fine people at USPS decided to run some drop tests on the box. It failed. The box was busted and taped back together. "Received in Damaged Condition" my foot. The transformers were a little beat up cosmetically. Don't know if they are electrically damaged until wired up.

Get to do soldering, wiring and electrical circuitry stuff again. Whee.

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For the life of me, I'll never understand why people can't appropriately pack items for shipping.
 
I believe the transformers were packed properly. They made the trip from Heyboer to me. From me back to Heyboer. Did not make the third trip. In all fairness, four of them has a combined weight of over 24 lbs. I suspect someone underestimated the weight of the box while handling and dropped it.
 
I believe the transformers were packed properly. They made the trip from Heyboer to me. From me back to Heyboer. Did not make the third trip. In all fairness, four of them has a combined weight of over 24 lbs. I suspect someone underestimated the weight of the box while handling and dropped it.
I collect antique phonographs which can be very delicate and sometimes very challenging to ship. A consequence of inadequate packing will result in damage, sometimes severe. We all need to understand that shipping is generally subjected to automation which includes conveyors and drops of several feet. I can't tell you how many reports (myself included) I've seen/heard of inadequate packing causing severe damage to expensive items.

All I'm saying is people need to package items carefully and securely. I don't blame the handlers for the end result of destruction due to negligent/inadequate packing.

I've learned to demand specific requirements of my sellers/shippers, as to how items must be boxed to withstand armageddon. If they don't comply I won't buy from them. Why would anyone choose to ship something they sell, just to guarantee it arrives damaged?

I mean no disrespect, but it's very easy to ensure an item can survive the rigors of shipping.
 
Rookie mistake. :o

So, I've been burning in the amp for a few days now. The sound became clearer. However, the volume remained fairly low. Upon checking the components versus the schematic, I discovered that all the 1K resistors were actually 100K. What??? Turned out I ordered the correct resistor value. However, the shop picked the 100K resistors and labeled the bag as 1K.

Just ordered the correct value resistors from Mouser. Will not get them until Wednesday.

In the mean time, I got started on the second one. Getting a little better at wire routing. :)
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Yeah, I find it’s always better to start with the 2nd amp. Eliminates all the mistakes I would have made on the first one😀
 
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