SmartSDR v3.9.19 and the SmartSDR v3.9.19 Release Notes
SmartSDR v2.12.1 and the SmartSDR v2.12.1 Release Notes
The latest 4O3A Genius Product Software and Firmware
Need technical support from FlexRadio? It's as simple as Creating a HelpDesk ticket.
Flex 6600M keying Henry 3K Premier amplifier.

Simple question, how do I key the Henry amplifier safely? The amplifier keys by a ground closure. It has +26 volts on the key line.
73,
Steve KD2OM
Comments
-
Good luck on this one.. As I remember from some years ago, the Henry used a large open pole relay with no suppressor diode across the coil thus one heavy back surge when keying.. My best to your radio keying circuit.. Jim K4JAF
0 -
Hi Steve,
I have keyed a Henry 2K and a SB200 amp with my 5000 and 6600. I built a little circuit in a small box to go between the Flex and the amp. It was just a junkbox 12V relay and a couple other parts. The relay contacts connect to the amp. I believe I used a couple of transistors and a couple resistors. Probably an easier way but I used what I had.
A friend keys his older amp with one of these: https://www.dxengineering.com/parts/ame-arb-704
Hope this helps!
73, Mark K5XH
0 -
Thanks Mark,
I found a solution that I already had but forgot about. I have a Denkovi USB relay board that the 6600M recognizes. I just configured one of the relays to key the amplifier.
I looked into the ARB-704, that probably would have been the next step.
73,
Steve KD2OM
0 -
Harbach Electronics sells a small Keying Interface circuit board that protects sensitive HF radios from
high-voltage Keying energy in older Heathkit amplifiers.
https://harbachelectronics.com/0
Leave a Comment
Categories
- All Categories
- 335 Community Topics
- 2.1K New Ideas
- 602 The Flea Market
- 7.9K Software
- 6.2K SmartSDR for Windows
- 169 SmartSDR for Maestro and M models
- 400 SmartSDR for Mac
- 263 SmartSDR for iOS
- 247 SmartSDR CAT
- 184 DAX
- 371 SmartSDR API
- 9.1K Radios and Accessories
- 17 Aurora
- 181 FLEX-8000 Signature Series
- 7.1K FLEX-6000 Signature Series
- 913 Maestro
- 53 FlexControl
- 857 FLEX Series (Legacy) Radios
- 882 Genius Products
- 447 Power Genius XL Amplifier
- 319 Tuner Genius XL
- 116 Antenna Genius
- 280 Shack Infrastructure
- 196 Networking
- 441 Remote Operation (SmartLink)
- 137 Contesting
- 736 Peripherals & Station Integration
- 137 Amateur Radio Interests
- 950 Third-Party Software