I hate the RCA 630 chassis

[Kamakiri]

Could probably recruit help at ETF......

[Kevin Kuehn]

Any chance the original mica's were kept so you can revert back to square one?

I think it's unlikely that replacing those inter-stage mica's would completely blow the picture off frequency.

[miniman82]

Do I need to bring my alignment rig to the meet and do some teaching?

[zenithfan1]

That's a good idea Nick, I'd like to be there for that as well but am stuck in Wisconsin this year.

[Gleb]

I could advise you to check the IF transformers with an ohmmeter, you might disturb their pins while recapping. If even one of the windings gets opened, you loose the signal completely.
BTW, I've never seen a bad interstage mica.

[Montman]

Has anyone with an RCA 8TS30 had to order those wire wound power resistors and the riveted in voltage divider? I'm having problems finding replacements and just what to order for a work around.

[N2IXK]

Originally Posted by Montman

Has anyone with an RCA 8TS30 had to order those wire wound power resistors and the riveted in voltage divider? I'm having problems finding replacements and just what to order for a work around.

Generally, I use 1.5 K and 250 ohm 25W Ohmite 210 series adjustable wirewounds to replace the 2 sections of R185. Both resistors will stack perfectly end to end on the original mounting hardware. Set the adjustable tap bands to get the odd values of resistance needed. Order the mounting washer kits (p/n 7PA25) with the resistors, as the OD of the new resistors is smaller than the original.

The riveted in "candohm" resistor (R186) can be replaced with a pair of chassis mount 10W power resistors (Ohmite HS10 series or similar). I use 6.8K and 100 ohms, as the closest standard values, with no problems. You will need to drill new mounting holes, after removing the original resistor.

[Kamakiri]

Ohhhh yes. In fact, I do that every time I rebuild an 8TS30. This may help

[bandersen]

That's what I did too. Notice the sliders are near the extremes to get 1360 and 230.
Next time around though I think I'll use a 1.5K and 250 ohm fixed and parallel them with resistors to get the exact value. Fixed are half the cost of the adjustable ones.

15K in parallel with the 1.5K
2.7K in parallel with the 250

2W should be enough. Most of the current will be running through the big power resistor.

[benman94]

I used a 1.5k and 15k resistors in parallel for the 1360 ohm, and 390 ohms in parallel with 560 ohms for the 230 ohm resistor.

[Montman]

Great suggestions guys. What company is best to purchase from?

[Montman]

What did you do for the R209? The 5300 segment is open. The connection is on the middle of the three pronges at the top. Is that 5300 + 500 for 5800 ohms since the three top pronges are for the 500 ohms and the connection is on the middle pronge. What value is it? 5300 or 5800 ? And any suggestions for best place to get it.

Thanks Bandersen for the pix. I try do nice work too.


What's the difference between the 8TS30, not the 6TS30. The schematics look the same.

[N2IXK]

Originally Posted by Montman

What did you do for the R209? The 5300 segment is open. The connection is on the middle of the three pronges at the top. Is that 5300 + 500 for 5800 ohms since the three top pronges are for the 500 ohms and the connection is on the middle pronge. What value is it? 5300 or 5800 ? And any suggestions for best place to get it.

R209 is 3 series connected sections, 5300, 500, and 500 ohms. The middle tap (default setting) is at 5300+500, or 5800 ohms. Possible settings are 5300 (bottom tap), 5800 (middle tap), or 6300 (top tap). This is the horizontal linearity adjustment.

Could be replaced with a 6.8K 50W adjustable wirewound, set for 5800 ohms. The original is only rated at 25 W, but a modern 50W unit is a closer mechanical fit to the original.

[benman94]

The 630TS has an electromagnetic ion trap; 8TS30 is PM. I think some of the 630TS sets have a field coil speaker; all of the 8TS30 sets, and most of the late production 630TS, should have a PM speaker.

[Kamakiri]

Some, but not all

My 8TS30 has an electromagnetic ion trap. Pm speaker tho.