I have been cleaning a bit and found a box of old lundahl transformers. Are these still interesting and what is an appropriate value to sell these for?
8 pcs SR501
3 pcs SR502
17 pcs SR503
2 pcs SR504
Information from lundahl website:
https://www.lundahltransformers.com/faq/
8 pcs SR501
3 pcs SR502
17 pcs SR503
2 pcs SR504
Information from lundahl website:
https://www.lundahltransformers.com/faq/
- SR501 is a high level 600 ohm : 600 ohm isolation transformer.
- in+ 1
- in- 5
- out+ 7
- out- 9
- Faraday shields 6+10
- SR502 is a high impedance bridging input transformer.
- in+ 1
- in- 5
- in centertap 3
- out+ 7
- out- 9
- Faraday shields 6+10
- SR503 is a line output transformer with turns ratio 1.4 : 1.
- in+ 8
- in- 6
- out+ 10
- out- 4
- SR504A is a microphone transformer 200 ohm : 2k
- 1 2 3 4
- SR504
- 5 6 7 8
- SR504 /SR504A PCB Flying leads
- in+ 2 red
- in- 3 yellow
- out+ 6 green
- out- 7 grey
- core 1
- housing 4
- Faraday shield 5+8 black
- SR504a is similar to the more modern transformer LL1538
They are surely still interesting as they are Lundahl's and tranformers don't age.
For value it's difficult to say, i've been using Lundahl's for 25 years now and never seen the ref you have , so they are definitely vintage!
I could be interested in some of them, depend on their ratings/spec ( for 501,502, 503 -and the 504a with leads as i already know their spec).
Do you know from which desk they come from ( i'm not sure they come from a desk but given the number and kind...)?
For value it's difficult to say, i've been using Lundahl's for 25 years now and never seen the ref you have , so they are definitely vintage!
I could be interested in some of them, depend on their ratings/spec ( for 501,502, 503 -and the 504a with leads as i already know their spec).
Do you know from which desk they come from ( i'm not sure they come from a desk but given the number and kind...)?
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Ok, got some more info about them: produced during 70's for Swedish radio/broadcast, so probably from a custom desk and could explain part number ( S(wedish) R(adio) 5XX).
I found a Reverb auction for a lot of the same kind for around 150€ for lot of twelve of them.
I found a Reverb auction for a lot of the same kind for around 150€ for lot of twelve of them.
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Thank you for your time. I also spotted that reverb auction with one single bidder. And found some other transformers (LL1527) sold on tradera.com (Swedish auction site) for about 30 € each. One pair sold on reverb for 40€ and i found a groupdiy.com user who sold a bunch of SR501 for 25€ each which seem to have disappeared quite fast in 2015... A bit but not a lot to go on 🙂
I don't really know anything about these either. Got them secondhand about 20 years ago with extremely limited information. So sadly no information on origin or previous use. They are desoldered from something...
More recent option like 1527 have multiple core (1+1/1+1) and as such offer more flexibility in use than the one you have at hand imho.
That said the 'vintage' vibe can have appeal to some... anyway those are surely great transformers if you are looking into 'transparent' transformers ( the bridging 30k/30k and the 600/600). The other thing is the broadcast field of use as they usually have lower bandwidth request than in studio (30hz/15khz).
The 1,4/1 idk: if gapped it could be used as a Marinair in Neve ba281 (1073/1272/1290/,...) as it is the same ratio but probably with a different 'sound'. If ungapped then idk, could be used as API but with less output level.
The 504 is ancestor to 1538 so anyone into mic input know they'll probably sound great.
I recently bought some 1517 from a fellow member here and they were in the 25 euro range. Not sure i would spend as much for the one you have for reason given.
Anyway once you decided on requested price contact me to see if we can arrange something.
That said the 'vintage' vibe can have appeal to some... anyway those are surely great transformers if you are looking into 'transparent' transformers ( the bridging 30k/30k and the 600/600). The other thing is the broadcast field of use as they usually have lower bandwidth request than in studio (30hz/15khz).
The 1,4/1 idk: if gapped it could be used as a Marinair in Neve ba281 (1073/1272/1290/,...) as it is the same ratio but probably with a different 'sound'. If ungapped then idk, could be used as API but with less output level.
The 504 is ancestor to 1538 so anyone into mic input know they'll probably sound great.
I recently bought some 1517 from a fellow member here and they were in the 25 euro range. Not sure i would spend as much for the one you have for reason given.
Anyway once you decided on requested price contact me to see if we can arrange something.