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Reviews For: Datong Automatic R.F. Speech Processor

Category: Audio Accessories for Transmitter & Receiver

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Review Summary For : Datong Automatic R.F. Speech Processor
Reviews: 3MSRP:
An English, high-quality, mic-level speech processor. This "RF" speech processor upconverts microphone audio to around 455 KHz for proper clipping and filtering, and then downcoverts the RF back to audio for input to a transmitter or transceiver. The highly effective RF processor offers mic level input and output adjustments and indicators, such as low and high Z mic input matching selection, mic input signal level indications of "LO" and "OK", and a built-in tone generator for proper mic-level audio output adjustment. It also features features fixed clipping levels of OFF, 0, 6, 12, 18, 24 and 30 dB.
Product is in production
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# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
IZ1FKS Rating: 2014-08-14
works with 756 pro 2 Time Owned: 3 to 6 months.
I have been using it for a few mounths, now I am able to enhance the average rf power output I found low on this rig (in comparison with my old ic-745 for example). I switched off the internal COMP. Since Datong ASP is built to be used with a dynamic microphone I modified it to use the icom hm-12. Anyway I have to selected high impedence on Rin selector in order to reduce the too loud signal coming form a electret condeser mic. Probably an attenuator should be designed and place i front of the asp input. Pay attention to ground loop with this unit, use battery or a dc supply different from the rig one (the rig ground and Datong ASP grounds need to be separated). If external power supply is used I suggest to change the rear dc jack connector with a connector adequate for supply in order to avoid polarity inversion (I damaged the rig mic input due to dc on jack)
GI0ZGB Rating: 2004-11-13
Quality Processor Time Owned: more than 12 months.
I owned two of these units way back in the eighties, sold the first then regretted parting with it. I still have the second for use on rigs that don't have, or have poor speech processing capabilities. I had a problem with RF feedback at one time, caused by a power supply ground loop. So I used a length of mini coax running from the PSU to the jack plug, but didn't connect the shield at the plug end, and this, breaking the loop, cured the problem completly. I think settings 6 & 12 would have been enough for local chat/DX & DX+QRM respectively, I can't recall using any other. It works well with a variety of mics, dynamic being best, keeping background noise to a minimum, my modified MC-90 (HQ Amplified) was brilliant. The quality of construction typical Datong - outstanding! Like my FL3 a unit worth keeping - highly recommended.
NL7W Rating: 2004-10-04
Super Effective Speech Processor Time Owned: more than 12 months.
Like other Datong ham radio products, it exceeded my initial expectations. I have noticed the unit does require approximately 0.5 to 1 second of voice to properly level out the processing and/or gain level. Once that is established, the clipping really makes a difference. Personally, I have found the 6 dB level quite useful for most all work on HF SSB. The 12 dB level could be used for DX'ing and pileups, but it verges on being just too harsh as I listen to my rig's great monitor circuit. Higher levels are effective, but unpleasant.

IMHO, this product outperforms today’s audio and DSP compressors. It is (was) a quality English product. Overall, it completes well against an American made Vomax split band RF processor from the same period.