High Voltage Non-HRM 100W Build Started

[Chris333]

Thanks Ken and Tom -- I will try Apex Jr. Usually if I try to order something over the phone when I'm not sure what to ask for, I get the wrong stuff. In hindsight, all the stuff I've tried so far has been the wrong stuff...


Chris

[David Root]

Bob-W, what is the capacitance of that coax? I like the18 ga conductor.

[Structo]

I didn't even measure the last stuff I got from Apex.

I was kind of afraid to, to tell the truth.

If it was high it would have bothered me enough to try and find lower pf cable.

The stuff I got was white teflon with a sort of brown looking insulator on the inner conductor.

Since Apex is a liquidator or surplus dealer, it seems you can never get the same exact wire the next time you order.

If I was smart, I would have ordered enough for several amps but the funds are low.

[David Root]

I just got mine from Steve, see pic. I bought 30 ft, measured the capacitance at 900 pF, so 30 pF/ft.

It is marked MIL-C-17F 12814 THERMAX RGU-142. 18 ga silver plated solid copper conductor, 100% braiding looks like solid silver (!). The OD is 3/16" and it's fairly rigid. It better sound good!

[Chris333]

I just got mine from Steve, see pic. I bought 30 ft, measured the capacitance at 900 pF, so 30 pF/ft.

It is marked MIL-C-17F 12814 THERMAX RGU-142. 18 ga silver plated solid copper conductor, 100% braiding looks like solid silver (!). The OD is 3/16" and it's fairly rigid. It better sound good!

I got some of that from Steve too, but haven't tried it yet. Pretty heavy, looks indestructible. Also got the RG-316 and RG-178, all MIL C-17D. Used some of the RG-178 (I think that's what I used, it's the thin white stuff) over the weekend. Compared to the coax I was using, it's a joy to work with. Not sure how it sounds since I made a bunch of other changes to the amp at the same time. Teflon is a must on shielded cable...

[David Root]

It has a double braided shield both braids are silver plated, it is top quality construction, I agree with you.

Our tax dollars at work! You could not buy this stuff "new" ie non-surplus for anywhere near 30 cents a foot.

[jelle]

David, I have that apexjr RG-142 stuff too. I have not tried it but it looks really good if you have the space to work with it. Very rigid. The white coax I sent you is much easier to work with. Please let me know if it sounds good.

Jelle

[David Root]

Jelle, I put some of your white NASA coax in the longer runs in my Bloozman HRM, actually the runs from the board to the HRM pots on the faceplate. Sounds great!. I have an intermittent problem in the FX loop I have to fix tomorrow. I think it's a jack.

I also changed the 1M and 500K bass pots to 250K as advised by Normster and no longer have a buttload o'bass, as Andy Fuchs so eloquently put it.

If you are building a Bluesmaster HRM, change both bass pots to 250K, you won't regret it!

[Cliff Schecht]

I've still got a good stash of 250k Log Allen Bradley pots (normal shaft length, new in box) if you guys are interested .