Our Team

At Signalert, our team of experienced portfolio managers, researchers and client service specialists will monitor the markets and manage your investments. We take the worry off your shoulders so you can focus on other important things such as family, career, and future aspirations.

Dr Marvin Appel

Dr. Marvin Appel


Marvin Appel is president of Signalert Asset Management in Great Neck, NY, which manages $200 million in client assets in mutual funds, exchange-traded funds and individual stocks and bonds using technical analysis and active asset allocation strategies.

Dr. Appel is also the editor of Systems and Forecasts, a highly regarded newsletter on technical analysis that his father, Gerald Appel, started in 1973. His books include “Higher Returns from Safe Investments: Using Bonds, Stocks and Options to Generate Lifetime Income” and “Investing with Exchange-Traded Funds Made Easy” (both published by Prentice-Hall). Dr. Appel and his father have also written, “Beating the Market, Three Months at a Time”, published by Prentice-Hall and released in January 2008.

Prior to joining the field of investment management, Marvin trained as an anaesthesiologist at Harvard Medical School and Johns Hopkins Hospital. He concurrently earned a PhD in Biomedical Engineering from Harvard University. Dr. Appel still maintains his medical licenses in New York and Maryland.

Dr. Appel is a member of the investment committee of the Northwell Health System (pro bono) and the advisory board of the Hospice Care Network.

Contact: mappel@signalert.com

Roni Greiff Nelson

Roni Greiff Nelson

Operations Manager/ Portfolio Manager

Roni began her career with Signalert in 1976 with founder, Gerald Appel. She has been overseeing the operations of the company alongside Dr. Marvin Appel since 2012. 

​In addition to the supervision of the day to day operations, Roni is the portfolio manager for client assets at TD Ameritrade and in variable annuities. She works closely with Donna Huber in providing our clients with the best customer care. 

Contact: rgn@signalert.com

Glenn Gortler

Glenn Gortler

Director of Research/ Portfolio Manager

Glenn began his career at Signalert in 1983 and became head of the subscription department for the Signalert investment newsletter “Systems & Forecasts” in 1990. 

​Under Gerald Appel’s apprenticeship, Glenn became Director of Research in 1995. Glenn worked together with the founder in developing Signalert’s proprietary statistical trading models that are still in use today. Today he works closely with the Dr. Marvin Appel and Joon Choi in researching and strategizing.  He also serves as portfolio manager for Signalert’s clients whose assets are at Charles Schwab and for one of Signalert’s investment partnerships.

Contact: ggortler@signalert.com

Joon Choi

Joon Choi

Portfolio Manager/ Research Analyst

Joon began his career with Signalert in 2001 as a research analyst. He has designed several of the firm’s investment strategies that are currently being utilized. Today, he continues to work with Dr. Marvin Appel and Glenn Gortler in researching and strategizing.

In addition to fund and research analysis, Joon is the portfolio manager of two of Signalert’s investment partnerships. Joon is a staff writer for Signalert’s investment newsletter, “Systems & Forecasts”. 

​Joon graduated from Colgate University with a degree in economics and mathematics. He received his graduate degree from Leonard N. Stern, NYU with an MBA in finance/Quantitative Analysis.

Contact: jchoi@signalert.com

Donna Huber

Donna Huber

Director of Client Services

Joining us in 1998, Donna manages all aspects of client services including opening accounts or transferring assets and working with clients’ lawyers or accountants as needed. ​

Donna works with brokerage houses and fund management for client accounts, prepares material for client presentations, and provides support for the executive team.

Having worked in commercial banks for 25 years, Donna is greatly experienced in the areas of administrative support for operations, customer service and office management. She provides our clients with the best customer care experience.

Contact: dhuber@signalert.com

Contact Us Today & Let Us Help You

Signalert Asset Management LLC

Phone: 516-829-6444
Toll Free: 844-829-6444

Email: clientservices@signalert.com