- Immersion heater. - 4 Updates
- Peavey Classic 60 questions - 8 Updates
- Not sure if I need a fuse - 1 Update
| "Ian Field" <gangprobing.alien@ntlworld.com>: Jan 17 06:40PM Thinking ahead just in case it blows............... The issue is length - I could measure the outside dimensions of the tank, but without taking the element out there's no guarantee there's no obstructions inside - and I could just measure the element if I took it out. The easy way out is to buy one of the shorter folded elements, but I'm wondering if the effect on convection would be good or bad. The tank is square, not cylindrical. Thanks for any help. |
| N_Cook <diverse@tcp.co.uk>: Jan 17 07:46PM On 17/01/2016 18:40, Ian Field wrote: > wondering if the effect on convection would be good or bad. > The tank is square, not cylindrical. > Thanks for any help. The other issue is undoing without deforming the ever thinner copper of the tank. Heat up the thread section with a blow lamp before attempting to undo . Moderate torque plus tapping spanner with hammer , before upping the torque. |
| "Ian Field" <gangprobing.alien@ntlworld.com>: Jan 17 10:23PM "N_Cook" <diverse@tcp.co.uk> wrote in message news:n7gqsv$71l$1@dont-email.me... > the tank. Heat up the thread section with a blow lamp before attempting to > undo . Moderate torque plus tapping spanner with hammer , before upping > the torque. The local DIY store offers a very flimsy looking pressed steel spanner that won't put enough torque on the element to do any damage. There's a more robust looking box spanner on Ebay that would apply the torque with less risk of buckling. The last element came out surprisingly easily - so I'm remaining optimistic. |
| Geo <nhhu-o3hu@dea.spamcon.org>: Jan 18 02:24PM On Sun, 17 Jan 2016 22:23:04 -0000, "Ian Field" >The last element came out surprisingly easily - so I'm remaining optimistic. What size was it back then?.. :-) I have a 27 inch element fitted at the top of a 42 inch cylinder. Water heating is normally by the CH coil but I occasionally test the immersion heater to make sure it works. The manufacture's leaflet states:- "... this heater will only effectively heat water ABOVE, it is important that the correct length be fitted, i.e. if an 18" heater is used in a 36" cylinder only 45-50% of the water will be heated" I have sensors at the top, 2/3 and 1/3 levels and a typical immersion heater test over a few hours shows that the tank is not fully heated. https://dl.dropboxusercontent.com/u/28554318/DECimmhtr.pdf |
| Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jan 18 06:55AM +1100 On 17/01/2016 3:04 PM, Phil Allison wrote: > http://profile.ultimate-guitar.com/profile_mojo_data/3/3/6/5/336564/pics/_c32086_image_0.jpg > Later versions have a full, perforated steel cover over all the > valves. **Two of the other output valves had very small cracks near the pins. I can only surmise that the owner had been rough in removing the valves (she admitted to doing so) and cracked the glass. -- Trevor Wilson www.rageaudio.com.au --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
| Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jan 18 07:00AM +1100 On 17/01/2016 7:02 AM, John Heath wrote: > hot in the same way you check the oil now and then in your car. > Speaking of this I need to get off the net and buy some antifreeze > :). **Since the amp is used professionally, I ran it under a test condition which was somewhat more rigorous and lengthy than normal. Following on from PA's suggestions, I fitted some 1 Ohm cathode resistors to each output valve and monitors the cathode current. It was within 10% for all valves. I consider that to be fine. The major problem with this amp (as with most of it's type) will be the owner. If she transports the foot pedal inside the amp again, then there is a high degree of risk of further damage. -- Trevor Wilson www.rageaudio.com.au --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
| Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jan 18 08:13AM +1100 On 17/01/2016 3:04 PM, Phil Allison wrote: > grids !! > http://www.radiomuseum.org/forum/tube_tester_avo_vcm_163_measurement_principle.html > Expensive too, working examples go on Ebay for up to $3000. **The transformers inside the thing are amazing things. They would be very expensive to produce today. Mind-numbing numbers of taps. -- Trevor Wilson www.rageaudio.com.au --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
| "Gareth Magennis" <sound.service@btconnect.com>: Jan 17 10:28PM "Trevor Wilson" wrote in message news:dg2em5Ftjq8U1@mid.individual.net... On 17/01/2016 3:04 PM, Phil Allison wrote: > grids !! > http://www.radiomuseum.org/forum/tube_tester_avo_vcm_163_measurement_principle.html > Expensive too, working examples go on Ebay for up to $3000. **The transformers inside the thing are amazing things. They would be very expensive to produce today. Mind-numbing numbers of taps. I built this thing and modified it to suit my needs for basic valve testing. http://triodeel.com/tester.htm I trust it more than anything I might buy off the Interweb that is going to be decades old. Gareth. |
| Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jan 18 10:56AM +1100 On 18/01/2016 9:28 AM, Gareth Magennis wrote: > http://triodeel.com/tester.htm > I trust it more than anything I might buy off the Interweb that is going > to be decades old. **Fair enough. However, the VCM163 is a VERY clever device, which could be done more cleverly today. That said, it is very convenient and it operating within specification. Except for the transformer switching, it is a very simple device at it's core. -- Trevor Wilson www.rageaudio.com.au --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
| jurb6006@gmail.com: Jan 17 07:09PM -0800 >"With transistor amps, the same idle current always flows in both >output devices cos they are connected in series. " I have wanted to pound a couple of things into people's heads about this for some time. What you say is true for idle current, the bias, but if there is an offset the current through the outputs is not equal. With no load it should be no matter what. Anyway, the sledge hammer is to beat it in that : 1. Adjust the bias first, with no load. 2. Adjust the balance/offset next, also with no load. Do this after having warmed it up a bit, if you can't, recheck it hot. If the manufacturer starts this shit about taking out jumpers to measure bias current, fuck all that. Just do the math and calculate it from the emitter resistors. Take my word for it. In fact I can adjust it with no spec. II can just feed it with low level program material and watch the waveform at the collector(s) of the voltage amp(s). The |¯|_|¯|_ in that waveform, produced when the feedback is taking care of the crossover distortion is the prime test point. Adjust bias to flatten that out, done. However, going farther, that is biasing it harder, does have some merit. First of all it is not that much, and it also gives the amp more low power damping factor. Believe me I know the difference. I am not talking going into class A here, I think that is stupid. If you are going to go class A go all the way and go SE. Then for the most part you only got even order distortion. |
| Phil Allison <pallison49@gmail.com>: Jan 17 08:59PM -0800 Trevor Wilson wrote: > be done more cleverly today. That said, it is very convenient and it > operating within specification. Except for the transformer switching, it > is a very simple device at it's core. ** Full article and internal pics here: http://schmid-mainz.de/Radio-Bygones_140.pdf One of the C-Core transformers is used with a half wave load, which could make it growl a bit and get hot after a while. BTW: Can it be used with valves that have anode caps ? Like the 6CM5, 6DQ6B, 807, 300B and 6146 types. .... Phil |
| Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jan 18 07:14PM +1100 On 18/01/2016 3:59 PM, Phil Allison wrote: >>>> valve testers, uses only AC voltages for ALL supplies - plates, >>>> screens and grids !! >>>> http://www.radiomuseum.org/forum/tube_tester_avo_vcm_163_measurement_principle.html Expensive too, working examples go on Ebay for up to $3000. > BTW: > Can it be used with valves that have anode caps ? > Like the 6CM5, 6DQ6B, 807, 300B and 6146 types. **No problems at all. Nuvistors are OK too. There is an adaptor, which is designed to take some really odd-ball valves, but, unfortunately, I didn't get one with my tester. I'll post some schematics to you tomorrow or Wednesday. The power transformers are a joy to behold. BTW: I reckon 3 Grand is cheap. Not that you couldn't buy a better machine for that kind of money, you can. It's just I scored a late model AVO 8 Mk7. Cost me $140.00. The original price was more than 2 Grand! It is surprisingly cheaply built. Based on what the AVO 8 originally cost, I reckon the VCM163 would be more like $15k, if it was still in production. It is very nicely hand built, in that typical, 1960s, Pommy way. -- Trevor Wilson www.rageaudio.com.au --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
| tyronedaniels549@gmail.com: Jan 17 10:22PM -0800 I have a insignia NS-39D400NA14.got good sound,tv comes on but the picture is only showing a blue screen with some faded lines through it |
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