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  #1  
Old 10-14-2019, 10:36 PM
vortalexfan vortalexfan is offline
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I've put in an order for 2 of the electrolytics and tomorrow I will be putting in an order for the rest of the capacitors I need for the TV.
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Old 10-21-2019, 12:42 AM
vortalexfan vortalexfan is offline
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OK, so I just figured out that that R28 a 1,000 Ohm 1/2 Watt Resistor and R93 a 15 Ohm 1/2 Watt resistor of which both serve as Bias Network Resistors were both way out of tolerance (way outside the +/-20% tolerance that those resistors were rated for) the 1,000 Ohm resistor measured at 1,488 Ohms, and the 15 Ohm Resistor measured at 32 Ohms, so with that in mind, would out of spec Bias Network Resistors cause the Low Voltage Rectifier to arc, and nearly redplate?

Also the 500 MFD 5 VDC Capacitor, aka the Bias Filter Cap measured at over a thousand MFD which means it was bad I'm guessing.

Also Is it normal for a brand new electrolytic capacitor to measure over 10% high in value? I'm asking because my brand new 470 MFD 16 VDC capacitor that was supposed to replace the old 500 MFD 5 VDC capacitor measured at over 520 MFD as opposed to 470 MFD.
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Old 10-22-2019, 08:00 PM
vortalexfan vortalexfan is offline
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well the rest of my capacitors came in the mail yesterday and I've been able to replace almost all of the capacitors in the TV except for the electrolytics that I hadn't replaced yet, and a few paper caps.

The thing thats holding me up is that 15 ohm 1/2 watt bias network resistor that had became a 32 Ohm resistor over time, its such an oddball value that I didn't even have any in my resistor stock that I had bought from radio shack before they closed up shop near me, and radio shack has that part and its only $1 and some change including tax which I would rather pay that for the part than having to pay $8 for the part (the price of the part including shipping and tax).

So no one on here has answered my question regarding the bias network resistors, would bad bias network resistors cause my low voltage rectifier tube to arc and redplate especially if they were drifted up in value way past the 20% tolerance range of the part?
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Old 10-23-2019, 12:02 AM
old_coot88 old_coot88 is offline
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Originally Posted by vortalexfan View Post

So no one on here has answered my question regarding the bias network resistors, would bad bias network resistors cause my low voltage rectifier tube to arc and redplate especially if they were drifted up in value way past the 20% tolerance range of the part?
No. If that 15Ω resistor (or any resistor 'downstream' of it it) drifts upward, it will not increase load on the 5U4. In fact if the 15Ω drifts upward, it will reduce the load very slightly. Conversely, if it were dead shorted (say the 500µf cap across it were shorted), it would increase the load very slightly.
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Old 10-23-2019, 08:25 AM
vortalexfan vortalexfan is offline
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Originally Posted by old_coot88 View Post
No. If that 15Ω resistor (or any resistor 'downstream' of it it) drifts upward, it will not increase load on the 5U4. In fact if the 15Ω drifts upward, it will reduce the load very slightly. Conversely, if it were dead shorted (say the 500µf cap across it were shorted), it would increase the load very slightly.
Ok, thanks. I was just making sure.
I will continue on with the recap process and replacing the resistor.
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Old 10-23-2019, 10:33 AM
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Quote:
Originally Posted by vortalexfan View Post
The thing thats holding me up is that 15 ohm 1/2 watt bias network resistor that had became a 32 Ohm resistor over time, its such an oddball value that I didn't even have any in my resistor stock that I had bought from radio shack before they closed up shop near me, and radio shack has that part and its only $1 and some change including tax which I would rather pay that for the part than having to pay $8 for the part (the price of the part including shipping and tax).
When ordering parts from online vendors the worst way to do it is to order 1-9 pieces of 1-9 different parts at a time....you don't hit volume price breaks and your paying $8 for parts that fit in a $1 greeting card envelope.

The best way to do it is to buy $100+ of parts once every 6-24 months, set it up so you stock 10-100 of each value cap and or resistor you may need for any set your likely to encounter. And only restock when you need enough of enough different parts to hit the price breaks on over a dozen things. Building that stock is expensive so start with the think you need most and every reorder pad with some parts you need less often until your stock is good...

If you buy 100 15ohm resistors at $0.05 a pop and had 32 other different parts on the same order then your 15ohm resistors cost $0.25 to ship divide that by 100 and each 15ohm resistor costs 2.5 cents to ship for a total investment of 7.5 cents per resistor...or $5.25 for 100 15ohm resistors. Now contrast that to radio shack at let's say $1 for 2 resistors...if you buy 100 resistors that is $50 throw in the gas to drive there and you are at over 10x the price of ordering in bulk online....

They will let you claim that $8 flat rate shipping option if you buy 2000 pieces (200 different part numbers at 100 pieces each part)...If you buy over 800 pieces online (regardless of whether it is 1 sample of each cap and resistor you could ever want or 800 identical parts) the shipping cost per part is less than 1cent...

I have been known to put some projects on hold for months till I need to fire off a large part order so 1-3 parts I don't stock can get nearly free shipping on a bulk restock order.

Radio shack and frequent small online orders you end up paying a lot for convenience...If you do a lot of resto work, money is tight and or a resto is not a rush job think about how much money you are throwing away on convenience...
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Old 10-23-2019, 12:57 PM
vortalexfan vortalexfan is offline
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Originally Posted by Electronic M View Post
When ordering parts from online vendors the worst way to do it is to order 1-9 pieces of 1-9 different parts at a time....you don't hit volume price breaks and your paying $8 for parts that fit in a $1 greeting card envelope.

The best way to do it is to buy $100+ of parts once every 6-24 months, set it up so you stock 10-100 of each value cap and or resistor you may need for any set your likely to encounter. And only restock when you need enough of enough different parts to hit the price breaks on over a dozen things. Building that stock is expensive so start with the think you need most and every reorder pad with some parts you need less often until your stock is good...

If you buy 100 15ohm resistors at $0.05 a pop and had 32 other different parts on the same order then your 15ohm resistors cost $0.25 to ship divide that by 100 and each 15ohm resistor costs 2.5 cents to ship for a total investment of 7.5 cents per resistor...or $5.25 for 100 15ohm resistors. Now contrast that to radio shack at let's say $1 for 2 resistors...if you buy 100 resistors that is $50 throw in the gas to drive there and you are at over 10x the price of ordering in bulk online....

They will let you claim that $8 flat rate shipping option if you buy 2000 pieces (200 different part numbers at 100 pieces each part)...If you buy over 800 pieces online (regardless of whether it is 1 sample of each cap and resistor you could ever want or 800 identical parts) the shipping cost per part is less than 1cent...

I have been known to put some projects on hold for months till I need to fire off a large part order so 1-3 parts I don't stock can get nearly free shipping on a bulk restock order.

Radio shack and frequent small online orders you end up paying a lot for convenience...If you do a lot of resto work, money is tight and or a resto is not a rush job think about how much money you are throwing away on convenience...
I understand what you are saying and I would seriously think about doing that if I didn't have such a tight budget to work with, and also the fact that I don't do enough repair jobs/restorations to warrant me stocking up on nearly 1000 parts just to get free shipping, it just isn't something I can do right now unfortunately.

Otherwise I would be doing what you suggested.
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Old 10-23-2019, 01:07 PM
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Kevin Kuehn Kevin Kuehn is offline
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I'm sure Mr M. remembers saving up his allowance so he could buy a handful of capacitors, back before he became independently wealthy.
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Old 10-23-2019, 01:46 PM
vortalexfan vortalexfan is offline
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I'm sure Mr M. remembers saving up his allowance so he could buy a handful of capacitors, back before he became independently wealthy.
Yeah, I wish that were the case for me. Unfortunately working part time as a custodian at an Amish themed restaurant doesn't pay as well you might think (although it pays much better than goodwill does.)
And then I just bought a new car that I took out a loan for so I have car payments so really it's not an option for me to be buying $300 worth of parts right now just to get free shipping.
So while I express that paying twice cost of the parts I needed in shipping is annoying, it's all I can do right now unfortunately.
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Old 10-23-2019, 01:41 PM
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Quote:
Originally Posted by vortalexfan View Post
I understand what you are saying and I would seriously think about doing that if I didn't have such a tight budget to work with, and also the fact that I don't do enough repair jobs/restorations to warrant me stocking up on nearly 1000 parts just to get free shipping, it just isn't something I can do right now unfortunately.

Otherwise I would be doing what you suggested.

I honestly have probably never hit the 800 part order threshold, but I do try to make my orders as few and big as I can to maximize price break and shipping ecconomy (read that minimize cost per item in my stock).

It isn't necessary to hit any of the volume price breaks... however planning buying to do as much of that as practical for you saves you money in the long run.

Not to sound rude but complaining about spending $8 shipping to get a single 10 cents part here in a week and prefering to spend $1 on a local part that should cost 10 cents seems like a logically conflicted argument. So a cheaper alternative was suggested.

When it comes to anything new I am as cheap as they come, and proud of it!
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Old 10-23-2019, 01:57 PM
vortalexfan vortalexfan is offline
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Originally Posted by Electronic M View Post
I honestly have probably never hit the 800 part order threshold, but I do try to make my orders as few and big as I can to maximize price break and shipping ecconomy (read that minimize cost per item in my stock).

It isn't necessary to hit any of the volume price breaks... however planning buying to do as much of that as practical for you saves you money in the long run.

Not to sound rude but complaining about spending $8 shipping to get a single 10 cents part here in a week and prefering to spend $1 on a local part that should cost 10 cents seems like a logically conflicted argument. So a cheaper alternative was suggested.

When it comes to anything new I am as cheap as they come, and proud of it!
Well the problem is that with digikey and Mouser, in order to get free shipping you have to make a minimum $80 order, and none of my orders ever reach that minimum.

Plus when I get old radios, record players or TVs to fix up, I never know what value of capacitors are going to be in it until I open it up or look up the service manual, and seeing as half the time when I get an old radio or record player from someone I don't know what the model is until it's in my hands.

So it's kind of hard to make a bulk order of capacitors when half the time I don't even know what I'm going to need until I get the radio, record player or tv.

So to me just ordering the capacitors once I know what I need makes more sense, seeing as no two radio, record player or TV circuits are the same when it comes to what parts they will need it's kind of hard to know what parts to order in bulk and what not to order in bulk.
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